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DTC P029:

Shift Solenoid Circuit:

CIRCUIT DESCRIPTION:
The PCM monitors the gear ratio and compares the ratio to the commanded gear ratio. If both ratios are not synchronized, Code P029 is set.

TEST CONDITION(S):
1. Codes P021, P022, P024, P028 and P056 not set.
2. Transaxle pressure switch indicating D1, D2, D3, or D4 position.
3. Engine running.
4. Vehicle speed 7 mph or greater.
5. Throttle position 15.7 degrees or greater.

FAILURE CONDITION(S):

Case 1:
a. Gear ratio between 0.65 and 0.71 for 5 seconds.
b. 1st gear commanded.

Case 2:
a. Gear ratio between 0.95 and 1.05 for 5 seconds
b. 2nd gear commanded.

Case 3:
a. Gear ratio between 1.54 and 1.71 for 5 seconds.
b. 3rd gear commanded.

Case 4:
a. Gear ratio between 2.87 and 3.11 for 5 seconds.
b. 4th gear commanded.

ACTION TAKEN:
1. PCM turns "ON" the "SERVICE ENGINE SOON" MIL.
2. PCM commands second gear when any forward gear is selected.
3. Garage shift adapts are maintained at current levels.

NOTES ON FAULT TREE:
1. Checking if Code P117 also set because it can cause other transaxle problems.
2. Checking if Shift "B" solenoid is "HI" when it should be "LO" or if it is "LO" when it should be "HI."
3. Checking if PCM operating correctly and setting code falsely.
4. Checking if CKT 750 is open to C111.
5. Checking if CKT 1223 is open.
6. Checking for a short to ground inside transaxle.
7. Checking for an open inside transaxle.