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DTC P094:

Shift Solenoid Circuit:

CIRCUIT DESCRIPTION:
This diagnostic test checks for a transaxle shift A solenoid problem by monitoring the commanded gear verses the transaxle gear ratio. If the gear ratio falls outside of the range for a given gear, Code P094 will set.

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

FAILURE CONDITION(S):

Case 1
1. Gear ratio between 1.54 and 1.71 for 2 seconds.
2. First gear commanded.

Case2
1. Gear ratio between 2.87 and 3.11 for 2 seconds.
2. Second gear commanded.

Case3
1. Gear ratio between 0.67 and 0.71 for 2 seconds.
2. Third gear commanded.

Case 4
1. Gear ratio between 0.95 and 1.05 for 2 seconds.
2. Fourth gear commanded.

ACTION TAKEN:
1. PCM turns "ON" the "SERVICE ENGINE SOON" MIL.
2. PCM allows only second gear when any forward gear is selected.

NOTES ON FAULT TREE:
1. Checking if Code P117 is also set because it can cause the transaxle problems.
2. Checking if Shift A solenoid is "HI" when it should be "LO" or if it is "LO" when it should be "HI."
3. Checking if PCM is operating correctly and setting code falsely.
4. Checking if CKT 750 is open to C111.
5. Checking if CKT 1222 is open.
6. Checking CKT 581 for a short to ground inside transaxle.
7. Checking for an open inside transaxle.