Error Code P1728

[Dennis G]

96 XLT - 5.0 Litre

The OD lifght was flashing and trans was jerking as though it was trying to shift into OD momentarily.  But, only at 60mph.  When slowed down to 40mph intermitent shifting went away.  But, OD light was still flashing.

Recovered Code # P1728 - Trans slip error - Converter Clutch Fault

Could this code mean my torqe converter is going out?

Reset codes.  Bronco runs fine for the moment.  All fluids up to normal.  Trans fluid shows no discoloration nor a burned smell.

 

[miesk5]

yo Dennis,

DTC P1728 "...indicates that the transmission is slipping. When the computer that controls the transmission detects a fault code like P1728, it will put the transmission into a "limp" mode. When you unhook the battery, the code is cleared and the transmission will function properly until the slippage occurs again. To resolve this problem, you will need to get your transmission overhauled..."

Source: by 2carpros.com

DTC P1728 - E4OD Transmission Control Indicator Lamp (TCIL) Flashing Diagnostic Trouble Codes 62, 628 and/or 1728 & transmission shifts hard for 90-96 TSB 98-4-19

Source: by Ford http://www.revbase.com/BBBMOTOR/TSb/DownloadPdf?id=43918

LIGHT TRUCK:

1989-97 F SUPER DUTY, F-250 HD, F-350

1989-98 ECONOLINE, F-150, F-250 LD

1990-96 BRONCO

1997-98 EXPEDITION

1998 NAVIGATOR

This TSB article is being republished in its entirety to correct the vehicles listed.

ISSUE:

Some vehicles may exhibit a flashing Transmission Control Indicator Lamp (TCIL) and Diagnostic Trouble Codes (DTCs) 62, 628, and/or 1728 may be stored in memory. These DTCs can be set by any internal transmission element slippage or potentially by torque converter slippage.

ACTION:

Refer to the following text when servicing these codes.

NOTE:

WHEN SERVICING A VEHICLE WITH A FLASHING TCIL WITH DTCS 62, 628 AND/OR 1728, DO NOT REPLACE THE TORQUE CONVERTER UNLESS PROPER DIAGNOSIS HAS PROVEN THE TORQUE CONVERTER TO BE THE CAUSE.

Always verify the customer concern. Proper diagnosis for DTCs 62, 628 and/or 1728 may require talking to the customer to find out if there were any other symptoms associated with the TCIL flashing, (i.e., shift concerns, erratic/early/late, proper torque converter operation, etc.), prior to noticing the TCIL flashing.

Prior to transmission repairs for DTCs 62, 628 and/or 1728 or investigating other causes, repair all non-related transmission DTCs first, then repair all other transmission DTCs other than 62, 628 and/or 1728.

=======

Find a good Transmission shop (one that friends, relatives and local police/fire dept uses) or Ford dealership to test the torque converter, shift solonoids, and do some line pressure tests in order to get to the root of the problem and then advise you on needed repair(s)

Torque converter clutch solenoid provides torque converter clutch control by shifting the converter clutch control valve to apply or release the torque converter clutch.

Symptoms: Failed on — engine stalls in drive at idle low speeds with brake applied or manual 2. Failed off — converter clutch never engages. May flash transmission control indicator lamp

 

[Dennis G]

Ok, will be pulling the pan in a few days to check if trans oil and/or filter has any nasty stuff in it first.

I would just take it in.  But, I am retired and budget is vey limited right now unless I win a lottery.

Thats an easy task to do and got access to a nice shop to do it in.

Will get back to you.



BTW: Sorry for the double posting.  Thanks for fixing that.

 

[miesk5]

yo Dennis,

I understand on being retired..

Also, I assumed that the P1728 is the only Code; if Not, let me know.

See this

96 Bronco-F-Series Workshop Manual (PARTIAL)

http://www.diesel-dave.com/vehic/manual/stj/stjleft.htm

I went through a lot of the

Section 07-01A: Transmission, Automatic, E4OD

DIAGNOSIS AND TESTING

Diagnosis by Symptoms and didn't see anything other than what was advised in the TSB:

Shift Concerns, •Feel Concerns

Harsh (Some/All)

Torque Converter Clutch Operation Concerns

•Cycling/Shudder/Chatter

242 — ELECTRICAL ROUTINE

Powertrain Control System

•Electrical inputs/outputs, vehicle harnesses, powertrain control module, torque converter solenoid, transmission range (TR) sensor, brake on/off switch, throttle position sensor

•Refer to Powertrain Control/Emissions Diagnosis Manual for diagnosis. Perform Torque Converter Engagement Test and Pinpoint Tests C and D using Rotunda Transmission Tester 007-00085, Cable and Overlay 007-00107 and the Transmission Range (TR) Sensor Cable "B" (MLPS Manual Lever Position Sensor Cable) 007-00086 or equivalents as outlined in this section. Clear codes, road test and rerun On-Board Diagnostics.

Speed Control Equipped Vehicles NOTE: Refer to Routine No. 212 before you proceed to No. 342.

342 — HYDRAULIC/MECHANICAL ROUTINE

Fluid Condition •Inspect fluid condition. If burnt or contaminated drain fluid from the transmission assembly and converter assembly. Check control attaching bolts for proper torque. Retighten as required. Record and erase On-Board Diagnostics codes. Bring vehicle to normal operating temperature. Perform Transmission Drive Cycle http://www.diesel-dave.com/vehic/manual/stj/stj71a15.htm#extract_1016

as outlined in this section. Perform On-Board Diagnostics. If condition still exists, continue diagnosis.

Main Controls (Valve Body)

•Bolts not tightened to specification

•Retighten bolts to specification.

•Torque converter clutch solenoid malfunction

•Refer to Electrical Routine No. 242.

•Gaskets damaged

•Inspect for damage and replace.

Pump Assembly

•Bolts not tightened to specification

•Retighten bolts to specification.

•Cross leaks

•Inspect for porosity/leaks, valve damage; replace pump as required.

•Gaskets damaged

•Inspect for damage and replace.

•Converter clutch regulator valve damaged

•Inspect for damage. Service as required.

Stator Support

•Teflon® seal on nose of stator damaged, cut, leaking

•Inspect for damage. Service as required.

Torque Converter Assembly

•End play (excessive), internal leakage

•Inspect according to procedures outlined in this section. Service as required.

 

[Dennis G]

Thanks for the great info.

Will pass this on to the guys that are going to be doing the work and get back to you here.

P1728 was the only code that came up.

 

[miesk5]

yo Dennis,

YW!Also, the Line Pressure Test is @ http://www.diesel-dave.com/vehic/manual/stj/stj71a21.htm#extract_1026

SPECIFICATIONS, including

Torque Specs

Band/Clutch

@ http://www.diesel-dave.com/vehic/manual/stj/stj71a55.htm

 

[Dennis G]

Got it.  Thank you.

Not sure what day we can get at this.  But, will try to keep you posted when we do.