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Trying to Understand how Rear Ending a Car could affect shift lock

After rear-ending another car yesterday, while I made a mess of the body around the front driver side tire, the shift lock would no longer disengage. Once overridden, that car happily changed gears, so I’m a little baffled on how the shift lock itself is affected.

Any thoughts?


When involved in a collision, every inch of a car is stressed, compressed, torqued and twisted…High-speed film of car wreck tests show a literal shock wave traveling through the vehicle structure…The damage is seldom confined to the visible crumpled sheet-metal…

For instance, salvage yards will tell you that automatic transmissions frequently are badly damaged in collisions even though they LOOK perfect, not a scratch on them…

In your photos, it looks like the L/F spring tower and been displaced (moved) inward. In a perfect world, the car should be totaled. But in this country, whether or not a wreck is totaled depends more on its model year and value than anything else…

True enough. I guess I was more surprised that it’d be possible to damage the shift lock without it being more evident; like not being able to change gears, for example. Thanks for your thoughts.

Correct me if I’m wrong (I have been before, and I will be again), but the shift interlock is just an electronic “wedge” that stops the shifter from moving. Over-riding it (mainly) consists of just ignoring it and moving the lever anyway. So regardless of damage to the transmission, you should still be able to shift out of park. I’d look more for damaged/blown fuses, cracked fuse panel, or loose wiring.

chaissos, that’s interesting, because I think the dash had the trunk light on mistakenly. Maybe I’ll luck out and that part will boil down to some kind of electrical problem. Granted, It would not surprise me if the spring tower was out of place too, so we’ll see.

Interesting thought, that does strike me as more likely than managing to break the shift lock in such a way that the rest of the transmission didn’t seem affected.

Excuse me if I inferred that khamer’s transmission was damaged…That’s unlikely…

It just might be.
At the last split second, when you realized your impending impact, you tromped on the brake pedal just as hard as your adrenalin would let you. This extra hard push, with impact added to that, may have displaced the brake light swith out of adjustment ( or even broken it ).

Try a re-adjustment or replacement of the brake light switch.

ken, I must have said something ambiguous; I meant the light on the dash that indicated the trunk was open was on, although the trunk was definitely not open and I could open and relatch it properly over and over. Thanks anyway, and I wouldn’t have thought about what stomping hell into the brake would do.

A possible answer to your inital query.

The brake light switch is what dis-engages the shift lock solenoid.

Oh, interesting. I didn’t realize those were connected like that.

Ergo, you have to have your foot on the brake to shift out of park.

Caddyman you really think that car should be totaled? From what I can see at most a control arm mite be bent. Not likely though. The tire is looks to be straight. I have fixed far worse hits than this and you could not tell the car was ever in a accident. As the problem of the shifter its most likely the brake light switch.

oldboyman, I can only hope that you’re right. The tire did look straight on to me as near as I can tell. When the car was being towed, both tires turned normally as well; I’d think major damage to the control arm would be fairly obvious when the wheel turns, but I don’t really know-- haven’t seen that kind of damage on a vehicle in person before.

Yes it would. I did see that the hubcap is damaged. So make sure that the rim gets ck out and balance the tire. I can tell you a control arm will bend first or the ball joint will brake. Rest easy this should be a easy fix.