Toyota key fob mystery

Personal Finances Buying and Maintaining a Car
1

This is a strange problem and I’m having trouble Googling the answer.

DS’s car, a 2008 Toyota Matrix, has a remote key fob. Said key fob will unlock the car, open the rear glass, and sound the horn for the panic button. What it will not do is lock the doors. I have replicated the problem with both key fobs; both behave the same way. The doors can be locked with the key.

So it would seem the problem is in the car itself. I’ve never seen just the lock function fail, while the unlock function still works. Y’all got any ideas?

Googling this returned many suggestions to replace the battery in the fob. There are other discussions on Toyota-centric forms where the fob fails completely. I can’t find anything where the fob works, sort of.

Regards,

  • HCF
    bumfuzzled
2

Swapping the batteries is always a good place to start… they’re cheap, easy, and at 14 years old (give or take), certainly nearing the end of their lives. It could just be the radio code for “lock” is longer than the codes for “unlock, trunk, panic,” and the battery doesn’t quite have enough juice to complete that one.

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3

Swapping the batteries is always a good place to start… they’re cheap, easy, and at 14 years old (give or take), certainly nearing the end of their lives. It could just be the radio code for “lock” is longer than the codes for “unlock, trunk, panic,” and the battery doesn’t quite have enough juice to complete that one.

I put a fresh battery in the key fob. No change. Car still will not lock remotely. Other functions work as expected.

Regards,

  • HCF
4

Bummer, that… Next step would be to “re-introduce” a fob to the car, on the assumption that they’ve lost track of what they believe the next code should be. The process is way too convoluted to put in a Fool post, so here’s a YT video https://www.youtube.com/watch?v=EeXy2bO_Oy8. If even that doesn’t work, I’d run it past a stealership’s service department :frowning:

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5

The receiver in the car has to send a pulse to activate the door locks. My money says that circuit/relay has worn out and failed. Just dumb luck whether it was lock, unlock, etc.