Hi....

My 97's key fob will usually not unlock the door from passenger side, although it works properly when locking, or if I'm at back of car or on driver's side. I've replaced the battery, cleaned out the fob insides and reprogrammed, and it still won't work consistently. Could it be the unlock button board on the fob or something in the door itself? Thank you.

 

???? which door does what? Will fob unlock drivers door? Does fob unlock passenger door, but not drivers? Fob should lock both doors at the same time.

 

Sorry, it's confusing. If I am standing on the driver's side or at the back of the car, I can press the unlock button and it works as it's supposed to, (one click to unlock driver door, then two clicks to unlock passenger door). HOWEVER, if I'm standing on the passenger side of the car, pushing the unlock button will not unlock either door. But locking works fine.

 

Moved to C5 Tech.

 

I guess you only have one fob. What kind off range do you have on drivers side? The fob is a transmitter so it sends the signal to the receiver box. The unlock button gets the most wear, they can lose range with age. I wound get a second fob and see what happens, before I would deal with receiver.

 

Vetteman: Thank you, sorry it was in the wrong spot.

Kevova: I do have another fob but it was never used. P put in a new battery and programmed it but it still isn't working at all so it's probably really dead. Are there receivers on both sides of car? Oh, and only about 2-3 feet range to unlock on driver's side, but standing at back of car, for locking, about 5-10 feet.

 

Not much range go with a fob. 1 receiver not cheap and behind dash.

 

Would would make it fail on one side of car only?

 

It doesn't have any range. It should be easily over 12 ft. But really 20+ for a new one.

 

FOB receiver is located behind drivers seat

 

Looks like something I can't fix myself. Thank you both for the advice.

 

The fob battery might be weak. As the previous diagram shows, the receiving antenna is located near the drivers rear wheel. If the doors work when standing near the driver's rear wheel but not on the passenger 's side (because it's further away), that would point to a weak fob battery which is limiting transmission distance.

 

Hi, no, the battery has been changed, and it does lock properly on both sides. It's only the unlock from passenger side that won't work.

 

I'm in the same crappy boat! Just bought this car now I'm worried.

 

I am in the exact same predicament with '99 coupe. Remote key fobs only work correctly when within about two feet of the receiver behind the driver's seat. This applies to three(!) key fob remotes: the two original ones cleaned - and previously working well, and one brand new one, all with new batteries (tested: 3.0 volts at installation). The head-scratcher: TPMS works fine - which seems to indicate that power/ground to the RFA is OK. Getting the "normal" U1096, 1064, and 1016 DIC codes (which I have read can be ignored - and which have been there even when the key fobs were working correctly; i.e. much longer range).

 

Has anybody made any progress in discovering a solution?
Current situation here on the '99 Coupe: I am becoming more convinced the problem is in the vehicle, rather than in the remote/key fobs. Reasoning: I went as far as to purchase a 'Xhorse' Remote Key Frequency tester; it indicates a good 300-320 MHz output from all three remotes (2 original ones, thoroughly cleaned, and 1 newly purchased one) - all with new batteries, which tested good at 3 Volts. My remote test also included the "double-click' of the 'Open' button (used to open the passenger door): got a "good" indication on each press - on all remotes.
To reiterate the problem here: all three key fob remotes work as expected, if - and only if - the key fob remote is within about 2 or 3 feet or so of the RFA receiver (located behind the driver's seat). It was eventually discovered that, at a greater distance, a SINGLE key press (any key) would work - and then no reponse to subsequent keypresses until about 30 seconds had gone by. Therefore no passenger door unlock which requires two 'Open' key presses within ten seconds. I finally tied a couple of observations together: the interior lights are supposed to turn on - and do - after an 'Open' cycle, and remain on for 30 seconds or until a door is opened. I closed the garage door (to be able to see the interior lights better) and experimented: with the key fob remote at the greater distance (about 10 feet in front of the car in this case), the car would respond correctly to ONE key press, and no more, UNTIL the interior lights went off, then it would respond to ONE key press again. Again: at close range, everything works fine.
I have tried disconnecting the vehicle battery for about 10 minutes, reconnecting it - while the fob(s) were far away, and then "re-learning" the fob/remotes. No help. Via the DIC Options, tried Approach Lights ON/OFF, Auto Unlock (all 3 options), Auto lock ON/OFF - all no help.
Don't mean to confuse things here, but: in my Internet searches, I came across one entry in a Corvette forum somewhere (can't find it again to save my life...) that mentioned something about a 30-second lockout, in reference to operation with the "passive entry" feature. For what it's worth, all of my key fob remotes have this feature disabled.
And during all of this, the TPMS tire pressure monitor - which shares the RFA receiver with the key fob remotes - has been working perfectly, as far as I can tell. So: why the 30-second period of not acting on a key fob press after the 1st one at long range - and why should "close range" override that? It's almost like the RFA receiver loses sensitivity - for 30 seconds... And - NO (zero) DIC fault/error messages...
Stumped...
Edit: I had also tried two successive "Unlock" commands in quick succession - from two different remotes. No help.
A test this morning revealed that the car would respond to two key fob/remote "Lock" commands in quick succession (but NOT two "Unlock" commands in quick succession). Note: after the transmission of a "Lock" command, the interior lights do NOT come on; this is expected, but it ties in with the 30-second period described earlier.

 

FIXED! (At least in my case...)
I was on the right track when I had mentioned "...RFA receiver loses sensitivty..." while the interior lights are on. One thing that can cause a perceived loss of sensitivity is interference; This ol' brain finally remembered swapping out the two lights in the cargo compartment with high-power LEDs - at roughly around the time that the key fob/remote problem started showing up. Some more Internet research provided evidence that LEDs can indeed be noisy suckers when it comes to radiated RF energy. I pulled the LEDs out of the sockets - and lo and behold - all key fobs now work 100% at long range! The LEDs proximity to the RFA receiver was no doubt a factor.