Mechanics

P1756 DTC - REPAIR?

2002 Dodge Durango

Drive Train Axles Bearings problem
2002 Dodge Durango V8 Two Wheel Drive Automatic 63000 miles

my wife's car. Check engine light and scanner shows P1756 - car also seems to start from a stop using second gear, not first

she says it's been " sluggish" off and on, but I first got the code yesterday

checked tranny fluid - all is good on color, smell and levels

seems like this is a possible solenoid issue? I cleared the code - maybe shouldn't have - wanted to see if it would come back, which it hasn't after several stops (short distances) - car is still sluggish accelerating from a stop - but otherwise upshifting / downshifting etc is all good and no slipping

I do have the mfgr and extended warranty but my nearby dealer is just about the worst in terms of avoiding warranty repairs and/or simply trying to rip me off whenever I needed to bring the car in for a dealer repair - it's probably expired anyway it was a 5/70 plan

any thoughts?
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Avatar
Rmanet
May 9, 2009.




It is most likely your governor pressure solenoid. If you have the 5 year/70000 miles, you are out of warranty.

Here is the diagnostic. But you have to have an NGC scan tool to properly perform the steps.
DTC P1756: GOV PRESS NOT EQUAL TO TARGET @ 15-20 PSI (GASOLINE)

Possible Cause
The following items may be area of concern: Other transmission-related DTCs are set.
Solenoid pack connector 5-volt supply circuit open.
Sensor signal circuit has short to ground, short to voltage or open.
Governor pressure sensor defective.
Transmission fluid burnt or oil pan contains excessive debris.
Governor pressure out of range.
Transmission leaking internally.
Defective PCM.
Defective valve body.

Diagnostic Procedure
1. Using scan tool, read DTCs. If good trip counter for DTC P1756 is not displayed or displayed count is not zero, go to step 25. If good trip counter is displayed and displayed count is zero, go to next step.
2. Repair any other transmission-related DTCs before proceeding. If no other transmission-related DTCs exist, go to next step.
3. Check transmission fluid for proper level and for any debris. Fill or repair transmission as necessary. If fluid level and condition are okay, go to next step.
4. Start engine. Allow engine to reach normal operating temperature. Set parking brake, depress brake pedal and place gearshift lever in " D" position. Using scan tool, observe governor pressure sensor pressure. If pressure is greater than 3 psi (.2 kg/cm 2 ), go to next step. If pressure is 3 psi (.2 kg/cm 2 ) or less, go to step 20.
5. Turn ignition off. Install a pressure gauge at transmission governor pressure test port. Start engine. With gearshift lever in " D" position, observe gauge pressure. If pressure is 5 psi (.3 kg/cm 2 ) or more, go to step 23. If pressure is less than 5 psi (.3 kg/cm 2 ), go to next step.
6. Turn ignition off. Disconnect transmission solenoid assembly connector. Turn ignition on. Measure voltage between ground and 5-volt supply circuit at transmission solenoid harness connector terminal No. 2. If voltage is 4.5-5.5 volts, go to next step. If voltage is not 4.5-5.5 volts, go to step 19.
7. Turn ignition off. Disconnect PCM harness connector C2 (White). Measure resistance of governor pressure sensor signal circuit between transmission solenoid harness connector terminal No. 4 and PCM harness connector C2 (White) terminal No. 29. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair governor pressure sensor signal circuit for open.
8. Disconnect PCM harness connector C1 (Black). Measure resistance of sensor ground circuit between transmission solenoid harness connector terminal No. 3 and PCM harness connector C1 (Black) terminal No. 4. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair sensor ground circuit for open.
9. Measure resistance of governor pressure sensor signal circuit between ground and transmission solenoid harness connector terminal No. 4. If resistance is less than 5 ohms, repair signal circuit for short to ground. If resistance is 5 ohms or more, go to next step.
10. Measure resistance between sensor signal circuit and sensor ground circuit at transmission solenoid harness connector terminals No. 3 and 4. If resistance is less than 5 ohms, repair governor pressure sensor circuit for short to sensor ground circuit. If resistance is 5 ohms or more, go to next step.
11. Turn ignition on. Measure voltage of governor pressure sensor signal circuit between ground and transmission solenoid assembly connector terminal No. 4. If voltage is one volt or less, go to next step. If voltage is more than one volt, repair sensor signal circuit for short to voltage.
12. Turn ignition off. Ensure transmission solenoid harness connector is disconnected. Remove transmission oil pan. Disconnect governor pressure/temperature sensor harness connector. Inspect connector and terminals for damage. Repair as necessary. Measure resistance of governor pressure sensor 5-volt supply circuit between governor pressure/temperature sensor harness connector terminal " A" and transmission solenoid harness connector terminal No. 2. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, replace transmission solenoid assembly (internal transmission harness).
13. Measure resistance of sensor ground circuit between governor pressure/temperature sensor harness connector terminal " D" and transmission solenoid harness connector terminal No. 3. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, replace transmission solenoid assembly (internal transmission harness).
14. Measure resistance of governor pressure sensor signal circuit between governor pressure/temperature sensor harness connector terminal " B" and transmission solenoid harness connector terminal No. 4. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, replace transmission solenoid assembly (internal transmission harness).
15. Measure resistance of governor pressure sensor signal circuit between ground and governor pressure/temperature sensor harness connector terminal " B". If resistance is less than 5 ohms, replace transmission solenoid assembly (internal transmission harness). If resistance is 5 ohms or more, go to next step.
16. Measure resistance between governor pressure sensor signal circuit and sensor ground circuit at governor pressure/temperature sensor harness connector terminals " B" and " D". If resistance is less than 5 ohms, replace transmission solenoid assembly (internal transmission harness). If resistance is 5 ohms or more, go to next step.
17. Reconnect transmission solenoid assembly harness connector. Turn ignition on. Measure voltage of governor pressure sensor signal circuit between ground and governor pressure/temperature sensor harness connector terminal " B". If voltage is more than one volt, replace transmission solenoid assembly (internal transmission harness). If voltage is one volt or less, go to next step.
18. Turn ignition off. Using DVOM, backprobe governor pressure sensor signal circuit at PCM harness connector C2 (White) terminal No. 29. Start and idle engine. Place gearshift lever in " N" position. Using scan tool, observe governor pressure sensor voltage. Compare scan tool value with DVOM voltage. If voltages match, replace governor pressure/temperature sensor. If voltages do not match, replace PCM.
19. Turn ignition off. Ensure transmission solenoid harness connector is disconnected. Disconnect PCM harness connector C2 (White). Measure resistance of 5-volt supply circuit between transmission solenoid harness connector terminal No. 2 and PCM harness connector C2 (White) terminal No. 31. If resistance is less than 5 ohms, replace PCM. If resistance is 5 ohms or more, repair 5-volt supply circuit for open.

NOTE: Removing transmission control relay in the following step may set other DTCs. Disregard these DTCs.

20. Ensure engine is at normal operating temperature. Place gearshift lever in " P" position. With engine running, remove transmission control relay from underhood Power Distribution Center (PDC) or Integrated Power Module (IPM), as applicable. Depress brake pedal and place gearshift lever in " D" position. Using scan tool, observe governor pressure sensor pressure. If pressure is 40-55 psi (2.8-3.9 kg/cm 2 ), go to next step. If pressure is not 40-55 psi (2.8-3.9 kg/cm 2 ), go to step 22.
21. Turn ignition off. Replace governor pressure solenoid. Test drive vehicle at 25-30 MPH. Using scan tool, monitor governor actual pressure and target pressure. If pressures do not remain constant within 5 psi (.3 kg/cm 2 ) of each other, repair internal transmission leakage problem. If pressures remain constant within 5 psi (.3 kg/cm 2 ) of each other, testing is complete.
22. Turn ignition off. Connect a 0-300 psi (0-21 kg/cm 2 ) pressure gauge to transmission governor pressure test port. Ensure engine and transmission are at normal operating temperature. Place gearshift lever in " P" position. Start and idle engine. With engine running, remove transmission control relay from underhood Power Distribution Center (PDC) or Integrated Power Module (IPM), as applicable. Depress brake pedal and place gearshift lever in " D" position. Observe governor pressure. If pressure is 40-55 psi (2.8-3.9 kg/cm 2 ), testing is complete. If pressure is not 40-55 psi (2.8-3.9 kg/cm 2 ), go to next step.
23. Turn engine off. Install transmission control relay. Drain transmission fluid and remove oil pan. Inspect pan for burnt oil and debris. Repair transmission as necessary. If transmission is okay, go to next step.
24. Replace governor pressure solenoid. Start engine. Observe gauge pressure. If pressure is less than 5 psi (.3 kg/cm 2 ), testing is complete. If pressure is 5 psi (.3 kg/cm 2 ) or more, replace valve body.
25. Conditions required to set DTC are currently not present. Inspect all applicable connectors and terminals for damage. Repair as necessary. Testing is complete.

Tiny
Zackman
May 10, 2009.


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