Ford F-450 and F-550 trucks equipped with the 5R110W transmission may store a variety of solenoid codes intermittently. In this case history the solenoids are good.
Once the solenoids have been verified good, the next step in the diagnosis process should be internal and external wiring checks because a vehicle’s wiring harnesses are more prone to producing intermittent codes than hard codes.
A visual approach to wiring is a good place to start, such as the internal wiring damage shown in Figure 1, but external wiring cannot always be accessible without some degree of vehicle disassembly. Checking resistance is valuable to determine if the wire is open or shorted but is not the definitive answer.
At this point the technician needs to know if the circuit can carry an electrical load. This can be accomplished with a power probe. If a power probe is not available, the good old fashioned method of attaching a headlamp to one end of the circuit and 12 volts to the other end should do the job. Load testing can expose a problem with wire damage as seen in Figure 2, which is caused by the wiring being tightly bundled and placed in chassis to body areas where body flexing or tension can result in chafing or wire strands being pulled apart.
With the F-450 and F-550 vehicles, the area where this short takes place can be difficult to find. The harness where this rubbing usually takes place is accessible from the driver’s side inner wheel well located near the shock tower and is rubbed by a sharp edge.
If the choice is made to repair the wiring damage, the harness will have to be accessible. It may be necessary to add length to the wiring to relieve tension or to reposition the harness to prevent chafing.
Mitsubishi Fuso trucks equipped with the M036A6 Aisin six-speed automatic transmission require a shift adapt reset procedure known as “Dealer Adjust.” This is done to allow the TCM to learn the new clutch clearances and clutch apply times to produce the proper transmission shift characteristics. Dealer Adjust should be performed whenever the transmission has been overhauled or replaced, or the TCM has been replaced.
The “Dealer Adjust” procedure is as follows:
- Remove the A/T diagnosis switch (5 amp fuse) as seen in Figure 3.
- Start the engine and bring the transmission up to normal operating temperature.
- Set parking brake.
- Apply foot brake, use LEFT FOOT.
- Make certain the OD switch, located on the shift lever, is OFF (light on dash is ON, see Figure 4).
- Move gear selector lever from “D” to “3.” This must be done three times within 10 seconds ending in the “D” position.
- The transmission temperature lamp will flash rapidly (Figure 4).
- Cycle the OD switch OFF, ON, OFF, OD, Off. Lamp should now be back ON. The transmission temperature lamp will now return to a slow, steady flash pattern. Four clutch engagements will be felt. This signifies the beginning of the learning process.
- When the transmission temperature lamp returns to flashing rapidly, increase engine rpm to 1,200. Cycle OD off switch OFF, ON, OFF. The OD off lamp should now be back ON. The transmission temperature lamp now returns to a slow steady flash pattern. One clutch engagement will now be felt. Part one of the learning process is now complete.
- When the transmission temperature lamp flashes rapidly, decrease engine rpm to an idle within 5 seconds.
- Move the shift lever to the reverse position and cycle the OD switch OFF, ON, OFF. The lamp should now be back ON and the transmission temperature lamp should now return to a slow steady flash pattern. Four clutch engagements will now be felt.
- When the transmission temperature lamp returns to a rapid flash pattern, increase engine rpm to 1,200. Cycle the OD switch OFF, ON, OFF, the OD Off. Lamp should now be back ON and the transmission temperature lamp will return to a slow flash pattern. A single clutch engagement will now be felt.
Part two of the learning procedure is now complete. - The transmission temperature lamp will now go out for 2 seconds and come back on for 1 second. This cycle will continue for three times.
- The “Dealer Adjust” procedure is now complete.
- Move the shift lever to the park position, reinstall the 5 amp fuse, recycle the ignition key. The OD Off lamp should now be OFF.
NOTE: If at any time the transmission temperature lamp goes out or stops flashing, restart the “Dealer Adjust” procedure from step 8.
The Dodge AS68RC transmission cooler lines are held into the cooler line fitting by retaining clips (Figure 5). These clips can be damaged or lost which means replacing them which creates a problem for the shop.
These retaining clips are larger than most applications using this type of retainer, which means new clips will have to be bought unless good used clips can be located.
These retaining clips are sold by the dealer only with the cooler line fitting to which they are secured. These cooler fittings are $86.25 each as of the time this bulletin was written.
Care should be exercised not to damage or lose the retaining clips. If they cannot be reused, new cooler line fittings will have to be acquired.
Cooler line fittings with retaining clips, #68020021AA
2005 and up GM trucks equipped with the 4L60/65/70E transmission may exhibit a complaint of torque converter slip when the vehicle is hot, accompanied by a Diagnostic Trouble Code P0894, component slip. This complaint is usually after overhaul and after the torque converter regulator valve bore repair.
The cause may be that during the rebuild process, the TCC PWM solenoid was not replaced, as the symptom mimicked that of a worn out TCC regulator bore, as shown in Figure 6.
A closer inspection of the solenoid snout, as shown in Figure 7, shows that a hairline crack caused a loss of solenoid pressure acting on the TCC regulator valve causing the torque converter to slip.
Replace the TCC PWM solenoid.
TCC PWM solenoid, GM part #24207054
Note: There are also aftermarket TCC PWM solenoids available. Contact your local supplier.
January 2018 Issue
Volume 35, No. 1
- Ford F-450 & F-550 trucks with 5R110W intermittent solenoid codes
- Mitsubishi Fuso FE & FG series ’05-10 code dealer adjust
- Dodge AS68RC: Cooler-line retaining clips
- GM 4L60/65/70E: P0894 transmission component slip
