Brake Issues

[B-Co Kid]

Im having more issues with braking. My yellow rear anti lock brake light is on (was on), but i disconnected the harness to the module.

After doing the pin test, i think my abs module is bad. Unless i get really lucky and find an abs module, what other options do i have

to restore decent brakes to my B-Co. When i hit the brakes, not slamming on the brakes, but pressing moderately, my tires makes a screeching

sound like i Am slamming on the brakes. I removed the harness connector from the abs to make the light go away, but the same

thing happens with it connnected or with it disconnected. is there anyway to bypass the abs and have regular brakes or any other option?

 

[Rons beast]

What are the particulars on your Bronc?

Generally you need to have the ABS read for codes, and repair according to that. Have the codes read.

On some older systems a false code can be set when there are other problems.

Your description sounds like your brakes are locking up. This is the exact condition that the abs is designed to prevent.

Are all 4 wheels locking? As if you did a panic stop with no abs, or are only the front or rear locking, or only one wheel?

Give us some more info and I'm sure the guys here will steer you in the right direction.

 

[B-Co Kid]

What are the particulars on your Bronc?

Generally you need to have the ABS read for codes, and repair according to that. Have the codes read.

On some older systems a false code can be set when there are other problems.

Your description sounds like your brakes are locking up. This is the exact condition that the abs is designed to prevent.

Are all 4 wheels locking? As if you did a panic stop with no abs, or are only the front or rear locking, or only one wheel?

Give us some more info and I'm sure the guys here will steer you in the right direction.

87 B-Co 351W. 5.8L. Automatic 3 speed trans.

Its hard to tell exactly which wheel locks up, but when trying to listen its only one rear locking up.

Just purchased a ABS controle module from donor B-Co. I will be purchasing another ABS hydraulic module also, that way

the entire ABS system will be new. Will post updates when everything is installed.

 

[miesk5]

yo B,

As Ron advised; hook up the ABS again an do this self-test;

RABS Self Test; except 93-96; "...The possible flashout codes are listed and explained in the Flash Codes Chart. Note that Codes 1 and 16 are not used.

Flashout Codes

Whenever the yellow REAR ABS light comes on during normal operation, a flashout code may be obtained to aid in problem diagnosis. If the vehicle is shut off before the code is read from a RABS-I module, the code will be lost. In some cases, the code may reappear when the vehicle is restarted. In other cases, the vehicle may have to be driven to reproduce the problem and, if the problem was associated with an intermittent condition, it may be difficult to reproduce. Therefore, whenever possible, it is recommended that the code be read before the vehicle is shut off. RABS II modules have been designed with Keep Alive Memory to preserve stored codes during key-off, and are to be used to service all prior year RABS I systems, except for 1987 and 1988 Bronco II vehicles.

WARNING: PLACE BLOCKS BEHIND THE REAR WHEELS AND IN FRONT OF THE FRONT WHEELS TO PREVENT THE VEHICLE FROM MOVING WHILE THE FLASHOUT CODE IS BEING TAKEN.

NOTE: If the red BRAKE light is also on, due to a grounding of the fluid level circuit (perhaps low brake fluid), no flashout code will be flashed and the REAR ABS light will remain on steadily.

NOTE: If there is more than one system fault only the first recognized flashout code may be obtained.

Obtaining the Flashout Code

A flashout code may be obtained only when the yellow REAR ABS light is on. No code will be flashed if the system is OK. There are certain faults (those associated with the fluid level switch or loss of power to the module) that will cause the system to be deactivated and the REAR ABS light to be illuminated, but will not provide a diagnostic flashout code.

Before obtaining the flashout code, drive the vehicle to a level area, and place the shift lever in PARK for automatic transmissions and NEUTRAL for manual transmissions.

Notice whether the red BRAKE light is on or not (for future reference) and then apply the parking brake.

If a RABS(-1) module is installed, keep the ignition key in the ON position so that the code will not be lost. RABS II modules have been designed with Keep Alive Memory to preserve stored codes during key-off, and are to be used to service all prior year RABS I systems, except for 1987 and 1988 Bronco II vehicles.

WARNING: PLACE BLOCKS BEHIND THE REAR WHEELS AND IN FRONT OF THE FRONT WHEELS TO PREVENT THE VEHICLE FROM MOVING WHILE THE FLASHOUT CODE IS BEING TAKEN.

To obtain the flashout code, locate the RABS diagnostic connector (with the Bk/Or wire), and attach a jumper wire to it. Momentarily ground it to the chassis. When the ground is made and then broken, the REAR ABS light should begin to flash.

NOTE: If the red BRAKE light was on (as noticed before the parking brake was applied), the problem may be with the low fluid level circuit and, in this case, no flashout code will be flashed and the light will remain on steadily.

The code consists of a number of short flashes and ends with a long flash. Count the short flashes and include the following long flash in the count to obtain the code number. For example, three short flashes followed by one long flash indicates Flashout Code Four. The code will continue to repeat itself until the key is turned off. It is recommended that the code be verified by reading it several times. In addition, the first code flashed may be too short because it may have been started in the middle. It should be ignored..."

RABS Codes



by Ford via Steve83

RABS Self Test Diagnostic Connector Location pic in an 88; "...it is next to the brake pedal which this is a picture of and is C111; It has the one wire that is black/orange.."

Source: by Jem270

 

[B-Co Kid]

yo B,

As Ron advised; hook up the ABS again an do this self-test;

RABS Self Test; except 93-96; "...The possible flashout codes are listed and explained in the Flash Codes Chart. Note that Codes 1 and 16 are not used.

Flashout Codes

Whenever the yellow REAR ABS light comes on during normal operation, a flashout code may be obtained to aid in problem diagnosis. If the vehicle is shut off before the code is read from a RABS-I module, the code will be lost. In some cases, the code may reappear when the vehicle is restarted. In other cases, the vehicle may have to be driven to reproduce the problem and, if the problem was associated with an intermittent condition, it may be difficult to reproduce. Therefore, whenever possible, it is recommended that the code be read before the vehicle is shut off. RABS II modules have been designed with Keep Alive Memory to preserve stored codes during key-off, and are to be used to service all prior year RABS I systems, except for 1987 and 1988 Bronco II vehicles.

WARNING: PLACE BLOCKS BEHIND THE REAR WHEELS AND IN FRONT OF THE FRONT WHEELS TO PREVENT THE VEHICLE FROM MOVING WHILE THE FLASHOUT CODE IS BEING TAKEN.

NOTE: If the red BRAKE light is also on, due to a grounding of the fluid level circuit (perhaps low brake fluid), no flashout code will be flashed and the REAR ABS light will remain on steadily.

NOTE: If there is more than one system fault only the first recognized flashout code may be obtained.

Obtaining the Flashout Code

A flashout code may be obtained only when the yellow REAR ABS light is on. No code will be flashed if the system is OK. There are certain faults (those associated with the fluid level switch or loss of power to the module) that will cause the system to be deactivated and the REAR ABS light to be illuminated, but will not provide a diagnostic flashout code.

Before obtaining the flashout code, drive the vehicle to a level area, and place the shift lever in PARK for automatic transmissions and NEUTRAL for manual transmissions.

Notice whether the red BRAKE light is on or not (for future reference) and then apply the parking brake.

If a RABS(-1) module is installed, keep the ignition key in the ON position so that the code will not be lost. RABS II modules have been designed with Keep Alive Memory to preserve stored codes during key-off, and are to be used to service all prior year RABS I systems, except for 1987 and 1988 Bronco II vehicles.

WARNING: PLACE BLOCKS BEHIND THE REAR WHEELS AND IN FRONT OF THE FRONT WHEELS TO PREVENT THE VEHICLE FROM MOVING WHILE THE FLASHOUT CODE IS BEING TAKEN.

To obtain the flashout code, locate the RABS diagnostic connector (with the Bk/Or wire), and attach a jumper wire to it. Momentarily ground it to the chassis. When the ground is made and then broken, the REAR ABS light should begin to flash.

NOTE: If the red BRAKE light was on (as noticed before the parking brake was applied), the problem may be with the low fluid level circuit and, in this case, no flashout code will be flashed and the light will remain on steadily.

The code consists of a number of short flashes and ends with a long flash. Count the short flashes and include the following long flash in the count to obtain the code number. For example, three short flashes followed by one long flash indicates Flashout Code Four. The code will continue to repeat itself until the key is turned off. It is recommended that the code be verified by reading it several times. In addition, the first code flashed may be too short because it may have been started in the middle. It should be ignored..."

RABS Codes



by Ford via Steve83

RABS Self Test Diagnostic Connector Location pic in an 88; "...it is next to the brake pedal which this is a picture of and is C111; It has the one wire that is black/orange.."

Source: by Jem270

miesk,

I did the ABS self test and the flash code was 7. You advised me in another forum to proceed with diagnosing my fault code 7

with the following:

miesk5, on 03 March 2011 - 09:58 AM, said:

yo, for the RABS; from Chilton On-Line via most local Public Libraries (need you Card's Bar Code Number to enter site via you Library)

Rear anti-lock brake system testing-except 1993-96 Bronco models

CODE 7 Troubleshooting; inclides connector Pin-Outs

http://content.chiltonsonline.com/content/images/8492/images/84929116.pdf

http://content.chiltonsonline.com/content/images/8492/images/84929117.pdf

I did that and my result was:

Posted 04 March 2011 - 07:22 AM

So i did the Pinpoint Code 7 test. After all was said and done, apparently i have a short in circuit 599 (PK/LGrn) between the module

and the RABS valve. It instructs me to repair the short and then proceed. Does this mean i have a bad ABS Module? When i tested the

resistence on the ABS Hydraulic unit, it was greater than 3 ohms, which is normal. So its not the hydraulic unit.

When i tested resistence at pin 13 on the abs module there was no reading (0.L) which is infinity or something right?

Im not very good with multi-meter stuff, but i think that means an open circuit or something. At normal, it should read greater than 10 ohms.

**and thats where im at now. I just purchased a donor control module, in case its the module. and i will be replacing the hydraulic module also.

any other suggestions?

 

[miesk5]

yo B

OK, I missed seeing that post, sorry!

re:

So i did the Pinpoint Code 7 test. After all was said and done, apparently i have a short in circuit 599 (PK/LGrn) between the module and the RABS valve.

It instructs me to repair the short and then proceed. Does this mean i have a bad ABS Module?

No, not a bad Module; it means Circuit 599(PK/LGrn) wire or terminal inside a connector is pinched against a metal piece such as the frame or wire or terminal in connector is against connector valve, etc. IT does Not Mean the Module is bad

------

When i tested the resistence on the ABS Hydraulic unit, it was greater than 3 ohms, which is normal. So its not the hydraulic unit. What step was this in? Guessing it is Step 7.3 WITH Valve Connector Disconnected; if so, we go to Step 7.4 with valve connector still Disconnected

--------------

When i tested resistence at pin 13 on the abs module there was no reading (0.L) which is infinity or something right?

That is infinity meaning there is an open between components being measured, another way of saying there isn't continuity? What step was this in? if this is in Step 7.1, it says to measure resistance between PIN 13 and chassis ground; so infinity will have you go to step 7.2 because there is a concflict of Information

 

 

and in the other Post;

you wrote; "Another question i have is about the black and orange(BK/O)RABS Self Test Diagnostic Connector, is it suppose to be connected back to something, because mine was not connected to anything?" Yes, it needs to be connected and I guess you did connect it to pin #12 of RABS Module?

?

 

[B-Co Kid]

yo B

OK, I missed seeing that post, sorry!

re:

So i did the Pinpoint Code 7 test. After all was said and done, apparently i have a short in circuit 599 (PK/LGrn) between the module and the RABS valve.

It instructs me to repair the short and then proceed. Does this mean i have a bad ABS Module?

No, not a bad Module; it means Circuit 599(PK/LGrn) wire or terminal inside a connector is pinched against a metal piece such as the frame or wire or terminal in connector is against connector valve, etc. IT does Not Mean the Module is bad

------

When i tested the resistence on the ABS Hydraulic unit, it was greater than 3 ohms, which is normal. So its not the hydraulic unit. What step was this in? Guessing it is Step 7.3 WITH Valve Connector Disconnected; if so, we go to Step 7.4 with valve connector still Disconnected

--------------

When i tested resistence at pin 13 on the abs module there was no reading (0.L) which is infinity or something right?

That is infinity meaning there is an open between components being measured, another way of saying there isn't continuity? What step was this in? if this is in Step 7.1, it says to measure resistance between PIN 13 and chassis ground; so infinity will have you go to step 7.2 because there is a concflict of Information

 

 

and in the other Post;

you wrote; "Another question i have is about the black and orange(BK/O)RABS Self Test Diagnostic Connector is it suppose to be connected back to something, because mine was not connected to anything?" Yes, it needs to be connected and I guess you did connect it to pin #12 of RABS Module?

?

 

When i tested the resistence on the ABS Hydraulic unit, it was greater than 3 ohms, which is normal. So its not the hydraulic unit. What step was this in? Guessing it is Step 7.3 WITH Valve Connector Disconnected; if so, we go to Step 7.4 with valve connector still Disconnected

 

yes, that was in step 7.3, and then i proceeded to step 7.4

 

 

When i tested resistence at pin 13 on the abs module there was no reading (0.L) which is infinity or something right?

That is infinity meaning there is an open between components being measured, another way of saying there isn't continuity? What step was this in? if this is in Step 7.1, it says to measure resistance between PIN 13 and chassis ground; so infinity will have you go to step 7.2 because there is a concflict of Information

 

When i measured resistence at pin 13 (in step 7.4) there was the 0.L reading. I made a mistake when i wrote "At normal, it should read greater than 10 ohms"

 

 

so, i guess what i need to check is the wire (PK/LG) and terminals in the abs module connector at pin 13??

also, about the black and orange(BK/O)RABS Self Test Diagnostic Connector, how/where do i connect it to the ABS module (pin 12)?? The (BK/o)Self Test Diagnostic Connector is located by the park brake, the ABS module is located in the middle of the dash. Is there a connection by the park brake to connect it to, bcuz i

didnt see anything. A disconnected RABS Self Test Diagnostic Connector, could that be the source of my ABS problems?

 

[miesk5]

ok

Iggie all the codes

Have to confirm how you got any Codes with

BK/O RABS Self Test Diagnostic Connector Not COnnected to RABS Module

Look at Chilton diagram http://content.chiltonsonline.com/content/images/8492/images/84929116.pdf

Pin 12 is next to 13 and it should have the BK/O wire attached\Check Module Harness Connector.. looking at it's pin that would plug into Module... is the BK/O wire or part of it in the there?

Maybe a prev owner cut it off for some reason?

 

[miesk5]

yo From Chilton again

http://content.chiltonsonline.com/content/images/8492/images/84929089.pdf

BK/O is ckt 571, next to ckt 599 PK/LG

So, the BK/O has to be wired into it's Pin at Module..forget the Parking Brake...

 

[miesk5]

I have to roll now; I don't have apic of your year's ABS Module connector to see how I can better describe where the wire goes; can you take pics and post them here?

as long as you can snap some and Xfer them to your PC; then you can do this as my friend Seabronc wrote for me;

"When I attach a picture from "My Pictures", I use the "Full Editor" function when replying to a post. When you use the "Full Editor" it has an Attachments with a Browse button. The "Browse" button will let you go to any file that you can get to from your local computer. Once you have selected a picture to upload, click on "OPEN". That will put a location in the attachments window. You then click on "Attach This File" and it will upload that picture when you press the "Post" button. You can attach multiple files by just continuing to "Browse and Attach" before you post.

"

 

[B-Co Kid]

I have to roll now; I don't have apic of your year's ABS Module connector to see how I can better describe where the wire goes; can you take pics and post them here?

as long as you can snap some and Xfer them to your PC; then you can do this as my friend Seabronc wrote for me;

"When I attach a picture from "My Pictures", I use the "Full Editor" function when replying to a post. When you use the "Full Editor" it has an Attachments with a Browse button. The "Browse" button will let you go to any file that you can get to from your local computer. Once you have selected a picture to upload, click on "OPEN". That will put a location in the attachments window. You then click on "Attach This File" and it will upload that picture when you press the "Post" button. You can attach multiple files by just continuing to "Browse and Attach" before you post.

"

This is how i was able to do the self test:

Posted 04 March 2011 - 05:25 AM by miesk5

yo,

RABS Self Test Diagnostic Connector Location; "...It comes out of a large loom under the dash, coming through the firewall, near the parking brake. On mine there are 2 similar connectors in that area, the correct one has only 1 black & orange (BK/O) wire running to it, & was hidden on top of the loom"

so, im not sure where the mix up was, but the way i did the ABS Diagnostic was using the wire by the parking brake.

And my question about the (BK/O) Self Test wire, that comes thru the loom by the parking brake... does that single (BK/O)wire supposed to be connected back to anything? I was not referring to the harness connector that connects to the ABS Module. But i will also try to post pics.

P.S.

i just want to say Thank You for taking the time to help me out. I appreciate it.

 

[miesk5]

yo, YW,

Yes, check the PK/LG for contact aginst driver side frame Rail just behind #1 Crossmember and follow it back.

I haven't heard back from anyone about the usual short locations for this ckt.

But here is a tip for another issue but relevant to finding the short;

Insulation Shrunk TSB 89-08-12 for 87 Bronco & F Series; "...Wire insulation may shrink away from terminals at ... connectors of the...wire harness.....Shrinkage is caused by high ambient engine temperatures and grease filled connectors. ACTION: Check for exposed wire at the terminals and wrap with electrical tape if required.



see how Ford changes Nomenclature from ABS to Anti-Skid Brake TEST in upper right of the diagram?



RABS valve pic by Steve83; Fits all '87-96 pickups and '87-92 Broncos

========

re; does that single (BK/O)wire supposed to be connected back to anything?

NO, it just stays as you found it, the conenctor lays on or in harness and does not connect to anything.

Sorry, I was dense on your previous Question(s) about this.

 

[B-Co Kid]

yo, YW,

Yes, check the PK/LG for contact aginst driver side frame Rail just behind #1 Crossmember and follow it back.

I haven't heard back from anyone about the usual short locations for this ckt.

But here is a tip for another issue but relevant to finding the short;

Insulation Shrunk TSB 89-08-12 for 87 Bronco & F Series; "...Wire insulation may shrink away from terminals at ... connectors of the...wire harness.....Shrinkage is caused by high ambient engine temperatures and grease filled connectors. ACTION: Check for exposed wire at the terminals and wrap with electrical tape if required.



see how Ford changes Nomenclature from ABS to Anti-Skid Brake TEST in upper right of the diagram?



RABS valve pic by Steve83; Fits all '87-96 pickups and '87-92 Broncos

========

re; does that single (BK/O)wire supposed to be connected back to anything?

NO, it just stays as you found it, the conenctor lays on or in harness and does not connect to anything.

Sorry, I was dense on your previous Question(s) about this.

Ok so here's the latest, received a newish ABS Module today. I hooked it up, started the engine and the yellow rear anti-lock brake light

went off. Woo hoo! Then, a couple seconds later it came back on. Damn! So i did the ABS check, and the code came back as 2 (one short blink

and one long blink). Kinda confusing... but just to bring everything back up to speed, with the original ABS module, the error code was 7

code #7: Shorted isolation valve or defective ABS module

with the replacement ABS moduel the code is 2

code #2: Open isolation valve circuit or defective ABS module

Note: Both ABS modules (original and newish one) are identical part numbers. The new one was tested 100% functional

now, by process of elimination, i conclude that a "defective ABS module" cant be the problem, since i just replaced it.

and the only other thing it could be is the isolation valve (according to code #2 and code #7).

so, should i just look to replace the hydraulic module, or should i be trying to find an alternate solution?

also, i checked the wiring along the frame rail, and i didnt see any exposed wires there or anything that could cause a short,

so that rules that out. i think miesk5 suggested checking the connections in the engine bay, due to shrinkage of the plastic around the wiring.

heat cause the plastic over the wire to shrink and expose the wire, and potentially causes problems.

Well, i checked the wire connectors that did have the shrinkage and the wire exposed,

but none of them pertained to the ABS system.

any suggestions?

 

[miesk5]

yo,

Call local dealer and ask if their current promo for free brake inspection also includes the Test for Codes. Something went askew during your first vs 2nd tests

The code consists of a number of short flashes and ends with a long flash.

Count the short flashes and include the following long flash in the count to obtain the code number.

For example, your One short flash followed by one long flash indicates Flashout Code 2

as for previous Codes; dunno why there is a differenc now; could be the ABS module connector pins or...?

RABS Code 2 Pin-Point Test in an 88; & Self Test; Click NEXT to view all pages; miesk5 Note; for all Resistance tests, battery needs to be disconnected; remove Negative cable at battery Source: by Jem270 at SuperMotors.net



NEXT page:

 

[B-Co Kid]

yo,

Call local dealer and ask if their current promo for free brake inspection also includes the Test for Codes. Something went askew during your first vs 2nd tests

The code consists of a number of short flashes and ends with a long flash.

Count the short flashes and include the following long flash in the count to obtain the code number.

For example, your One short flash followed by one long flash indicates Flashout Code 2

as for previous Codes; dunno why there is a differenc now; could be the ABS module connector pins or...?

RABS Code 2 Pin-Point Test in an 88; & Self Test; Click NEXT to view all pages; miesk5 Note; for all Resistance tests, battery needs to be disconnected; remove Negative cable at battery Source: by Jem270 at SuperMotors.net



NEXT page:

thanks miesk5, i couldnt find the code 2 pin test procedure. I'll give it a try later today.