Does your car have either Active Handling or an Autodimming rearview mirror?

You will notice in the wiring diagram I provided, that there is a second wire that comes off of Pin F9 that goes to to the ABS. On Active Handling equipped vehicles only, the ABS module uses an input from the backup switch.

I'm not sure if autodimming mirrors were even a factory option in 2000, but they don't show up in the manual I have to look at here. But on later MY of Vettes, the backup lamp circuit coming off of the relay has a second wire that leads to the autodimming mirror, to turn it off when the car is in reverse.

As a quick check, I might suggest individually unplugging the reverse switch connector, the connector off the ABS and the connector from the autodimming mirror, to see which device is at fault.

 

Well as an update, I removed the Micro Perim Relay, and with car off and the key on run, found the following voltages:

30 - 0.00 Volt
85 - 0.00 Volt
86 - 12.4 Volt
87 - 12.3 Volt
87A - 11.1 Volt but somewhat variable.

Seems 87A is the circuit coming from the Trans Switch. In normal condition, the relay should be set to that connection and there should be no power coming into 87A until reverse is engaged.

I guess the next step is to replace the switch and see if that does the trick.

Thanks ALOT!!

 

Before you go and replace the switch, please look at my last post and confirm if it has active handling and/or an auto dimming mirror and definitely pull the connectors individually and recheck for current at the relay connector.

Also, I believe the reverse switch is a ball check type switch that screws into the transmission case. I am curious if adjusting it (backing it out some or screwing it in further) has an affect.

 

After reading numerous posts on this & other C5 Forums re issues with LED reverse lights & LED underhood light, my thinking is this....Why look for trouble? Unless of course you do a lot of driving backwards....with your hood open

 

Thanks Electron. While 2000's did not have the auto rvm, I have added one just using the stock 4 wire harness. I do have the F45 magnetic shocks with the active handling.

I guess my thinking is, this backup switch is like $20 so seeing its the original, I might as well give it a shot. I do however think you are correct about it being sensitive to how deeply you adjust it. I figured I'd check continuity across the leads when installling to make sure its set correctly.

If this doesn't work, then its going to get tougher. Thanks again for your help!

 

Curious....Your new LED's are 80w. Isn't that too much for stock C5 electrical system? I believe OEM reverse bulbs are 27w.

 

I went Adjure and hi po bulbs (28 vs 21w) because I live in a rural area with no street lighting at all. The OEM set up was basically useless under those conditions. The Adjure alone is a big improvement. As to underhood lighting, yeah, I am with you there. I always have a powerful flashlight on board in case I need it though.

 

You guys are confusing the LED ratings. The reason why you run into issues with leakage like I am reporting here, and hyperflash, etc, is because LED's are so much more efficient and pull a much lower load. In my case here, the LED's are coming on very dimly to a small current which should NOT be there, that with the stock bulbs result in nothing.

When you see an 80 watt rating on LED's, that only refers to the equivalent output compared to the traditional incandescent you are replacing. For example, the stock 2057 bulbs draw ~27 watts which is around 2.25A. These 80 watt LED's draw approx 700mA which is over 3 times less.

The value of LED's are greater output, with less draw and heat. In my case, I live in a very rural area, big trees, etc, and it's impossible to see behind you with the stock set up. Going to the Adjure helped alot, but I did not want to risk going to a higher wattage and hotter incandescent bulb and risk heat damage. The LED's offer tremendously more output and run much cooler. A total win-win.

Regarding my issue, this is NOT an LED issue! This situation is merely warning me that I have an underlying issue that the stock incandescent were not sensitive enough to display. I'm actually happy that I'm getting to the root of the problem and taking care of the issue.

I hope this helps.

 

Many cars with this problem won't notice it until they install LED bulbs. If you have a parasitic power drain on your reverse light or hood circuit and don't know about it, that drain will substantially shorten the life of your battery. Better to know their is a problem and fix it than pretend it's not there.

Based on what I've seen with LEDs, the wattage is not based on actual power draw but a luminous comparison to an equivalent filament-type bulb. In this case, an 80w LED bulb would be roughly 3X as bright as the factory bulb.

 

I installed RadioFlyerInnovations.com' circuit easily under the dash of my C-5 last year primarily because it allowed the change from OEM bulbs to LED's a few at a time. Their system allows both bulb types to function. I also ran into the problem with the Amazon supplier and the bulb base discrepancy. I still have not finished the complete move to LED's. I will but he device that allows both bulb types. It well worth the cost of the device!

 

I think you're referring to the Hyperflash harness. This only affects the turn signals and maintains the factory turn signal flash rate. It does not have an effect on other circuits.

 

Thanks for the info!

I had a "situation" when I installed LED taillights. Loved the way they look, but for some strange reason the left outside light would always flicker or "bounce" when i activated directional signal. Then the entire brake light went out. Then it came back on again. Was about to return them. But just for the helluva it, I switched the left outside & left inside lights. (And keep in mind all 4 LED taillights are exactly the same). Guess what? No more issues! It's been over 2 yrs & they function perfectly! No one could figure out why.

 

I suspect it was the seating. The one negative historically of LED's has been quality control, especially on the base dimensions, and components. The good news is, it's gotten alot better. When matched against the old sockets, some of which might have some degree of heat damage, and have loosened up, sometimes the tolerance is a little out of range, and you run into flickering and other inconsistencies.

As someone mentioned above, sometimes cleaning the socket, and slightly sanding any imperfections on the contacts help. So, does simply swapping the LEDs to different sockets too. It's just a function of taking a close look and seeing if it's an easy fix. But again, the tolerance and quality of these LED products are getting better and better, so you don't see these kinds of problems as much anymore. But, it is important to also look at the old sockets to see if they might need some attention too. It's all about having a solid contact.

 

I understand what you're saying, however in the case of my taillights it actually doesn't apply, since each taillight is an integral unit....not individual led's that you would plug in.

 

Wasn't aware you were talking about sealed assemblies and not bulb replacements. In my rear Halo's, they used the stock sockets, so presumably a sloppy old heat distorted socket could affect the same scenario, but either way, I'm glad the simple swap solved the issue for you.

 

Thanks!
The sockets were in great condition. It was really strange, the Halo Taillight would work perfectly in other positions....so you would think it's not the Taillight, it's something with the vehicle. Yet when I swapped the 2 Taillights, it worked perfectly in that left outside position....so you would think it's not the vehicle, it's the Taillight. Weird!

 

I bought some yellow led's on ebay for mine. They are bright enough for me. Did it mostly for aesthetics' Thought they looked cool with my yellow vert. Cost around $10 with free shipping too. direct plug and play. very easy install. Put a yellow LED strip behind the bumper for the exhaust enhancer plate that I made myself too. Here is a few pictures of them on my vert.

 

The bulbs I bought are doing the same thing though they didn't at first or maybe I didn't notice it until my buddy told me my reverse lights were on while driving. So I put the stock bulbs back in for now. They didn't seem to make much difference anyway with the stock light housings.

 

Mine are not giving me any problems at all. Although mine is a 1999 if that makes any difference.

 

At this point I am almost certain its the backup switch. Either the switch itself or the adjustment (depth). My new AC Delco is sitting on my doorstep. It was $18 shipped from RockAuto. I will be able to confirm when I get back in town.