pshaw0629

Hi there,

I have a 1993 del sol with an auto transmission. It's on it's second aftermarket alarm system. I have a feeling this created the gremlin, but maybe not.....

At times, the trans will only get out of park when I ever-so-slightly tap the horn. I've replaced the trans interlock switch, and the mechanic is stumped.

So what happens is my foot's on the brake, car running, but shifter won't get out of park, as if my foot's not even on the brake. I tap the horn, boom, shifter is unlocked. This works EVERY TIME! But, the shifter isn't stuck every time either. I recently had another company remove the older alarm system when this started occurring, thinking the new alarm system would fix it. It didn't. But, the alarm system doesn't lock the shifter - so I'm not sure if the alarm system is causing this issue....does anyone have any suggestions as to how I can attack solving this?

Thank you!

tony_2018

Diagnose the shift lock solenoid

mk378

First check that the brake lights work. That is what drives the solenoid. You should hear a click from the solenoid when you press and release the brake pedal in park. Someone may have cut the wire. In stock configuration, the only interaction between the horn and the brake lights is they share the same fuse under the hood.

pshaw0629

And that's been the challenge to fixing this, is that maybe every third time we try to get out of park, we have to beep the horn, otherwise it works as you'd expect it to! So that would eliminate a wire being cut, correct, since it doesn't do it every time?

I'll try to start the car in the garage from now on, with the door down, to see if the brake lights illuminate if I can't get out of park.