Key fob issue

[Baked]

I have a 2000 GTS and keep running into the same issue. Half of the time my fob's do not work to lock/unlock the doors. I put new batteries in both of them so that is not the issue.
One minute, they work and the next time I go to lock the door it no longer works. I've held both buttons down to reset them. Sometimes that works, other times it has no effect at all.

Any thoughts?

 

[dave6666]

Standard issue reply it seems with these problems is how old is the battery in the car?

When they do work does the horn chirp on arm? The red light on the dash blink? The marker lights flash on dis-arm? Have you tried the magic hidden reset keyhole for grins? When the alarm does arm and you hear the horn and see the red light flash will it set it off by popping the hood?

 

[Baked]

The battery is only a couple of years old.
When it does work, yes the horn honks and the dash light blinks. The lights also flash on disarm. I've never tried setting the alarm off by popping the hood though so I'm not sure what happens with that. It just seems like the unit in the car wherever it is, just doesn't receive the signal all the time.

 

[Steve-Indy]

Have you noticed that this occurred in any specific geographic location? What about proximity to radio/TV transmission towers or high tension lines?? The above mentioned towers often rendered the alarm set function inactive on a friend's 2001..but if he placed his body between the tower and the fob, and stood near the windshield...it would work. I often experienced a similar problem in one area of a parking lot that had high tension lines on two sides.

Of course, you might also have a problematic alarm module...might be worth asking a Viper Tech to take a look at it.

 

[DrumrBoy]

I have the same problem. The fob that came with the car works sometimes. Seems location independent. The newer fob (purchased a couple of years ago) works all the time.

I wonder if the radio circuitry in the fob wonks on some fobs...either because of heat or dropping it or ????

I tried everything except the magic reset hole and just gave up on the original fob and use the newer one.

 

[Baked]

I'll have to pay attention next time it doesn't work to see if I'm around towers or lines. I'm not sure off hand. If that isn't the case, maybe I'll have to pick up a new fob.

 

[Steve-Indy]

If you have noticed any towers/lines...not likely an issue.

 

[Ron]

The frequency that our Viper alarms use for the FOB is not the typical automotive standard (forgot the actual numbers unfortunately, maybe 280MHz) and at least in the Indy market certain TV towers attenuate the signal dramatically as they are quite close in frequency. Also tricky is that the ground level power of the TV signal is not intuitive. Closer isn't stronger. It's more like a donut around the tower, so a mile or two away has a stronger influence than 1/2 mile away.

I solved my problem by moving the EEM module antenna from the console to the base of the windshield, spiral wrapped it into an old 35mm film cover, velcro'd to the driver side windshield and then place the FOB directly over it when I park in an area that the TV antenna has an impact. This is probably a 1996 & 1997 only trick as I think the later years had the antenna in the wiring harness not loose in the console. Especially important in 1996 & 1997 as there isn't a alarm key override in those year cars. In addition, the new style FOB's do seem more powerful therefore can more likely overpower any interference.