check engine light

I know when you have low fluids it can  activate the check engine light but my problem is a strange one . last week I hear bang bang bang in my right wheel well so here I pull over and a bungie cord with the hooks are stuck in my tire giving me a flat at the same time my check engine light went on and my scan tool is broke. the truck is running perfect  but when I start the truck  the light is off  while idleing it wont go on  but about a half mile after I start driving  the light activates and it wont go off until the truck is shut off. this is why im leaning toward  low fluids and it doesn't happen until everything gets warmed up and flowing but they are all fine. .does anyone know if the tranny fluid is low if that can activate the light?. I  checked the gas cap it on tight . I don't know if the stretching of the bungie cord while it was stuck in the tire hit wires under the truck or what or if it is just a coinsetence the light went on when the bungie cord was banging around while stuck in the tire .....thanks mike

Yo Mike,

95 full size with 5.8

Low fluid level will not directly cause cel to light. But these codes could be shown...

DTC 636 Transmission Fluid Temp (TFT) higher or lower than expected; "...Can be caused by a bad connector or harness (an open circuit, or short to Ground / Batt), or the transmission was overheated. Once you remove the pan locate the sensor in the valve body and remove the electrical connector very carefully. The sensor is about the size of a pen cap. To remove the sensor carefully unlock the stop tab and twist it, pull down to remove it. It comes out before a full quarter turn is made. Put it back in the reverse order. When you get the sensor to come out be prepared to catch the trans fluid that follows behind it, you will get less than a quart out of it. It is located in da Pack between Converter Clutch Control (CCC) Solenoid & the Coast Clutch Solenoid. try the connections first. They are usually the root of the problem..."

Source: by miesk5 at Ford Bronco Zone

DTC 637 - TOT sensor circuit above maximum voltage possible causes: Damaged TOT sensor. Open harness circuit(s). Damaged processor. or the transmission was overheated. The transmission fluid temperature sensor is located on the solenoid body assembly in the transmission sump. It is a temperature-sensitive device called a thermistor. The resistance value of the transmission fluid temperature sensor will vary with temperature change. The powertrain control module monitors voltage across the transmission fluid temperature sensor to determine the temperature of the transmission fluid. The powertrain control module uses this signal to determine whether a cold start shift schedule is necessary. The cold start shift schedule lowers shift speeds to allow for the reduced performance of cold engine operation. The powertrain control module also uses the transmission fluid temperature sensor input to adjust electronic pressure control pressure for temperature effects and inhibit torque converter clutch operation during the warm-up period. Symptoms: Torque converter clutch and stabilized shift schedule happens too soon after a cold start. Codes P1783 or 657 indicate transmission fluid temperature exceeds 132°C (270° F), results in increased EPC pressure and torque converter clutch engagement. May flash transmission control indicator lamp. Diagnostic Trouble Codes: 636, 637, 638, 657, P0712, P0713, P1711, P1783.

Source: by Ford via miesk5

***

Can you Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19

http://broncozone.com/topic/14269-code-reader/?pid=74587&mode=threaded

hi miesk 5 ...its always a pleasure to get feedback from you.something your wrote about the batt. ground caught my eye.  a while back when I posted about my right headlight  blinking on and off  you said about cleaning the ground at the lug which is  right next to the batt on the wheel well. .doing that did the trick  but for the past few weeks I been noticing sometimes when I put the headlight s on the left headlight would be very dim until I hit the brake pedal  to get the trans out of park  then it would go bright maybe I should clean these grounds up again and see if that cuts the CEL off. but its just odd  that  the CEL will not go on till I drive about  a quarter of  a mile or so. I think im just going to buy a new scanner thanks mike

Yo Mike,

TY!

Troubleshooting; "...If you have a problem when turning on one circuit it causes another to come on partially (dim lights, etc.), check the ground for the part or system that was turned on first. i.e., if you press the brake pedal & the parking lights turn on partially or fully, check the brake lights' ground; This is caused by current going thru da brake light bulb filaments & finding a ground in the parking lt. system instead of its own ground..." by me

Headlight, see this wiring diagram...

http://www.revbase.com/BBBMotor/Wd/DownloadPdf?id=46703

Left headlight uses different ground, g100, than right hl. So, take a look at it. There is a splice though between hl and g100. Will give you a location if you need it.

Check other grounds as well. On all battery and other cables/wires, look for corrosion on the cable or wire close to the connector, lug, etc. Sometime corrosion forms under the connector, lug, etc. As well as around each wire strand.

Locations & Components in a 96, about 99% same as your 95; G101 front of engine compartment, front of fender apron (D1) - RH = Passenger side mine has 2 small black wires between starter relay & headlight; this is #5 in the diagram; G100 & G104 (tied together in diagram); G100 @ LH front of engine compartment on upper radiator support; G104 @ Rear of LH fender apron near hood hinge and 4WABS Test Connector (RED); G100 Serves Component, LH Oxygen Sensor, Fuel Pump Module, Inertia Fuel Shutoff, Misfire Sensor, Misfire Sensor Shield, Output Shaft Speed (OSS) Sensor, Powertrain Control Module (PCM) 5.0L; G101 Serves, RH Oxygen Sensor; G104 Serves Component: 4WABS Control Module, 4WABS Data Link Connector, 4WABS Relay #1, Instrument Cluster, Powertrain Control Module (PCM) 5.8L, Powertrain Control Module (PCM) 5.8L, Programmable Speedometer/Odometer Module (PSOM), Trailer Relay Box; G103 (battery to engine) Lower RH front of engine serves Component, 4WABS Pump Motor, Battery, Data Link Connector (DLC), Mass Air Flow (MAF) Sensor, Powertrain Control Module (PCM) 5.0L, Powertrain Control Module (PCM) 5.8L, Right Front Park/Turn Lamp, Right Front Side Marker Lamp Right Headlamp; G201 Behind bottom of LH cowl panel (driver's side kick panel) Component, Compass/Outside Temperature Module, Day/Night Mirror, Inside Cargo Lamp, Left Power Lumbar Compressor Motor, Outside Cargo/High Mount Stop Lamps, Right Power Lumbar Compressor Motor, Seat Belt Switch, Door Lock Actuator (PDL & Probably Power Window Motor); G200 Behind bottom of RH cowl panel serves Component, Air Bag Diagnostic Monitor, Electronic Shift Control Module, Instrument Cluster, Programmable Speedometer/Odometer Module (PSOM), Remote/Keyless Entry Module, Speed Control Servo/Amplifier Assembly; G103 (battery to engine) Lower RH front of engine serves Component, 4WABS Pump Motor, Battery, Data Link Connector (DLC), Mass Air Flow (MAF) Sensor, Powertrain Control Module (PCM) 5.0L, Powertrain Control Module (PCM) 5.8L, Right Front Park/Turn Lamp, Right Front Side Marker Lamp, Right Headlamp; G400 Rear Window Defroster @ LH rear corner of cargo area, near rear lamp assembly; Engine Block pic in a 94 5.8; "...The black battery wire goes from the front bolt of the engine mount (on the block) to this tab & up to the battery post, where a smaller black wire goes to the core support, providing a continuous ground path between the engine, frame, battery, & body; Frame & Battery pic in a 93; "...With the wheelwell gone, it's easy to inspect the frame ground, just inboard of the spring tower on top of the frame rail. The battery ground cable is stripped ~3/4" and a tab is soldered on so it can be bolted to the frame; Intake Manifold to Block Strap Location in a 96 5.0 is between 2nd & 3rd plugs on passenger side; SEE DIAGRAMS

by me at...

http://broncozone.com/topic/20952-loose-ground/page__pid__109954__st__0&

Here are ground diagrams in your 95 5.8

http://www.revbase.com/BBBMotor/Wd/DownloadPdf?id=9877

And wiring diagrams, same as in Ford manuals,

http://www.revbase.com/BBBMotor/Wd

check engine light still coming on after driving  a half mile or so .like I said earlier the codes for egr  valve and sensor showed up on the scanner . I tested the egr valve  it is holding  when vacuum  is applied and releasing when not applied. the vacuum is good from the hose. .so I had a 20 dollar credit from autozone   and got the egr positioning sensor that's is mounted atop of the egr valve considering  it has never been replaced  .driving about a half mile and the check eng. light is on again.  the truck is running perfect..my next item im looking at is the egr solenoid  causing the problem. the scanner doesn't seem to have a code for that.thanks mike

Yo,

EVR Testing, Ford; "....check the filter on the solenoid (Fig. 4, EVR filter shown). If this is clogged it will inhibit the venting of the solenoid; "...EVR Solenoids should be 20 to 70 ohms (100 to 135 ohms for 7.5L engines). A functional test can be performed on most applications by using a Scan Tool. Enter the Output State check and cycle the accelerator pedal. This will turn all the solenoids on and off. Using a DVOM monitor the voltage at the EGR solenoid(s). They should toggle from a high voltage to a low voltage. Typically this is stated in the manuals and scan tools as above 10.5 volts to below 2 volts. If the voltage does not toggle make sure that you have system voltage on the power side of the connector. If system voltage is present and the voltage does not cycle to the low side check the connector and wiring to the PCM. If the wiring and connector are okay the problem may be in the pin at the PCM or the driver in the computer itself..." READ MUCH MORE by Tomco.

http://api.viglink.com/api/click?format=go&jsonp=vglnk_146522288551813&key=6ed47b392b9edfe394b9e89b72717104&libId=ip43v4f801000bgv000MA1iu273gw3y9lm&loc=http%3A%2F%2Fwww.fullsizebronco.com%2Fforum%2F7-1980-96-bronco-tech%2F423266-idle-egr-vacuum-issue-am-i-testing-correctly.html%23post6037818&v=1&out=http%3A%2F%2Fweb.archive.org%2Fweb%2F20110704111747%2Fhttp%3A%2F%2Fwww.tomco-inc.com%2FTech_Tips%2Fttt32.pdf&title=Idle%2FEGR%2FVacuum%20issue%20-%20am%20I%20testing%20correctly%3F%20-%20Ford%20Bronco%20Forum&txt=EVR%20Testing%2C%20Ford%3B%20%22....check%20the%20filter%20on%20the%20solenoid%20(Fig.%204%2C%20EVR%20filter%20shown).%20If%20this%20is%20clogged%20it%20will%20inhibit%20the%20v...

thank you so much for your input and the tomco info sheet...........you are the man.   ford needs you on their team    thanks again mike