The problem I have is with my 90 Honda Civic EX, auto tranny.

On cold mornings I can shift the car out of park and drive around normally, but when I stop and shift back to park it doesn't seem to go into park correctly. I can feel the tranny shifting into park and the car doesn't roll or anything, but the "P" light on the instrument cluster does not light up. Since the car doesn't realize the car is in Park then I can't get the key out and the shifter is locked in the park position. To get it out of park then I have to use a different key to press the manual shift lock release, but still can't get the key out of the ignition. When the thing works correctly I hear a clicking noise that sounds like it's coming from behind the dash, when it doens't work right don't here the clicking. I was thinking it might be some type of relay but I don't know, and I don't know where a relay might be located. Does anyone have any ideas? Oh yea, I first thought the problem might be related to the brake switch so checked to see if the brake lights are working when the problem happens, they are so that's not the problem.

Thanks in advance,

Erich

TxGreaseMonkey

Your Civic is equipped with the following devices to prevent inadvertent shifting:
. A/T selector with shift lock.
. Key cylinder with interlocked ignition key.

Shift Lock System:

The shift lock system prevents the shift lever from moving to R or D4 from the P position, unless the brake pedal is depressed and the accelerator is in its rest position.

Note:
. The shift lever cannot be shifted when the brake pedal and the accelerator are stepped on at the same time.
. In case of system malfunction, the shift lever can be released by pushing a key into the release slot near the shift lever.

Key Interlock System:

The ignition key cannot be removed from the ignition switch unless the shift lever is in the P position. When the shift lever is in any position other the P, a solenoid is activated, making it impossible for the key to be removed, until the shift lever is moved to the P position.


Therefore, you need to check for a faulty A/T gear position switch and possibly a faulty steering lock assembly (key interlock switch and key interlock solenoid). Take a test light or multimeter and also check all under-hood and under-dash fuses. These fuses can affect power going to the 8P connector and the interlock control unit. Check for good contact between the connector and socket terminals. If the problem remains, you may want to replace the interlock control unit. These are sophisticated, involved systems that can challenge the best technicians.