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No First gear Starts In Second Gear

1995 Jeep Grand Cherokee will not start in First gear,but starts and runs fine in second gear.

HOW TO START TROUBLESHOOTING THIS PROBLEM?

First of all you need to scan error codes stored in the Transmission control module(TCM).
Scan and see what fault codes are stored.To scan use  capable scan tool through the data link connector under the dash.
On your model jeep the trans is controlled by a standalone TCM .If the problem is transmission related then codes will be stored in TCM so if someone tries to check for codes using the data link connector under the hood they won't find anything.Because ECM( engine control module ) has no codes stored.

CAN IT BE FAULTY TCM OR ANY SPEED SENSOR?

Its very rare,very doubtful for TCM or any other sensor causing this problem.
As you mentioned in your problem description that  it takes off in second but all other shifts are ok then most likely the TCM is ok, and the output speed sensor will be too.


THEN WHAT CAN CAUSE THE PROBLEM?

The most likely cause of this would be a bad governor pressure transducer.

WHY GOVERNOR TRANSDUCER WILL CAUSE SUCH PROBLEM?


The governor transducer transfers data to the TCM about how much pressure is in the circuit. The TCM then controls the governor solenoid accordingly to control pressure.
Now when the transducer fail it  start reporting incorrect pressures to the TCM. If the pressure in the governor circuit has pressure in it when you come to a stop then the 1-2 shift valve won't return to the first gear position and you'll take off in second.

OK,WHERE IS THIS GOVERNOR TRANSDUCER LOCATED?

On 1995 jeep grand Cherokee the governor transducer is mounted on the right side of the valve body and its job is to tell the TCM about the exact pressure in the circuit.


ANY OTHER POSSIBILITY OTHER THEN GOVERNOR TRANSDUCER?

Another possibility can be the 1-2 shift valve in the valve body itself.May be it is actually stuck. This is possible but doesn't happen nearly as often as a failed transducer.So first confirm if transducer is working or not.

HOW CAN I CONFIRM THAT?


First get the TCM scanned.If you get no codes then monitor the governor pressure on a scan tool compared to what is shown with a manual gauge. If the two don't match and pressure is different then the transducer will need to be replaced.

One more basic test to confirm the transducer is working or not is,
come up to a stop, start to take off and drop the shifter into manual first. If this drops it to first gear then replace the transducer.

OK.WILL TRY THIS TEST'S.BUT WHERE IS TRANSDUCER LOCATED?

On 1995 Jeep Grand Cherokee the transducer is mounted on the right side of the valve body .Its towards the right of the filter.To replace the transducer it will take approx an hour.


So most probably its Transducer issue.But still get it confirmed by the above mentioned testing procedure before you get it replaced.

This details will help.
Thanks.


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