P0763 code - The 3-4 soenoid is actived when the transmission control module (TCM) determines that the transmission must shift into our of 4th gear. The solenoid is only actived during the shifting of the transmission. When the solenoid is actived, hydraulic pressure is applied to proper shift elements in the transmission to allow the desired shift. Once the shift is completed the solenoid is turned off. When monitored when both the 3-4 solenoid and the solenoid supply voltage is actived. Set condition when 3-4 solenoid is turned on and the TCM detecs of the following in the 3-4 solenoid control circuit : open, short to ground, short to voltage or faulty 3-4 solenoid control driver in the TCM.

Possible cause P0763 code:

- solenoid control circuit open

- solenoid control circuit shorted to ground

- solenoid control circuit shorted to another circuit

- 3-4 solenoid

- Transmission control module (TCM)

Diagnostic test P0763 code

Step 1. Check if the DTC is current

When the transmission control module (TCM) detecs and stores a DTC, the TCM also stores the vehicles operating conditions under which the DTC originally set. This information is located in the scan tool under environmental data. Before erasing any stored DTCs, record any available data to assist in duplicating the conditions which the DTC originally set.

Turn the ignition off to the lock position. Using the environmental data recorded earlier. Using the environmental data recorded earlier, try to duplicate the conditions in which the DTC originally set. It may be necessary to test drive the vehicle. with the scan tool, read transmission DTCs.

Did the DTC P0763 reset?

Yes, go to step 2.

No, go to step 6.

Step 2. Check the 3-4 solenoid control circuit for an open

Turn the ignition off to the lock position. Disconnect the TCM C2 harness connector and the trasmission electrohydraulic control unit assembly connector. Measure the resistance of the (T73) 3-4 Solenoid Control circuit between the TCM C2 harness connector and the Transmission Electrohydraulic Control Unit Assembly harness connector.

Is the resistance below 5.0 Ohms?

Yes, go to step 3.

No, repair the 3-4 Solenoid Control circuit for an open.

Step 3. Check the 3-4 solenoid control circuit for a short to ground

Measure the resistance between ground and the T73 3-4 solenoid control circuit.

Is the resistance below 5.0 Ohms ?

Yes, repair the 3-4 solenoid control circuit for a short to ground.

No, go to step 4.

Step 4. Check the 3-4 solenoid control circuit for a short to another circuit

Measure the resistance between the 3-4 solenoid control circuit and every other circuit in the transmission electrohydraulic control unit assembly harness connector.

Is the resistance below 5.0 Ohms between the 3-4 solenoid control circuit and any other circuits in the transmission electrohydraulic control unit assembly harness connector?

Yes, repair the 3-4 solenoid control circuit for a short to another circuits.

No, go to step 5.

Step 5. Check the 3-4 solenoid

Reconect the transmission electrohydraulic control unit assembly harness connector. Measure the resistance of the 3-4 solenoid between the 3-4 solenoid control circuit and the solenoid voltage supply circuit in the TCM C2 harness connector.

Is the resistance between 2.5 and 6.5 Ohm ?

Yes, using the schematics as a guide, check the transmission control module (TCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the TCM in accordance with the service information. Perform NAG1 Transmission Verification Test.

No, replace the 3-4 solenoid in accordance with the service information.

Step 6. Chek the wiring and connectors

The conditions necessary to set this DTC are not present at this time. Using the schematics as a guide, inspect the wiring and connectors specific to this circuit. Wiggle the wiring and connectors while checking for any possible open or shorted circuits. Check for any service information tune-ups or technical service bulletins that may apply.

Were there any problems found?

Yes, repair as necessary.

No, test complete.

P0763 3-4 solenoid circuit