Bret928

Ok am I missing something?

My "TAIL LAMP" warning light comes on comes on whenever I turn on my lights at night. Hit the reset and the master warning light in the gauge pod goes out. Leaving the central warning light on - until I hit the brakes.

Did a check of the lights (running, marker, fog, brake etc.) and they all seem to be working fine.

Again this only happens when I have the lights turn on – so I’m a bit confused why the tail light comes on but goes out when I hit the brakes.

Maybe my Shark has been hanging around my MG too long.

Anyway can someone tell me what am I missing here?

Big Dave

Just an FYI...the license plate lamps are on the same warning circuit.

Alan

I don't think so ... on any year...

Alan

Big Dave

Are you saying it's on a different circuit (if so, which one) or that the license plate lamps aren't on any warning circuit?

Alan

Dave - no warning for license plate bulbs - Porsche rationale - not a safety critical lighting function

Alan

Landseer

Rear marker lights and tails are together on the same circuit, though.

My tail light warning is also on. The Left rear marker light seems very bright, may be wrong bulb, which could cause the warning. Or, my bulb warning unit is bad I suspect (84)

Maybe that might help.

BTW, Alan has the major expertise, I am kind of focused on the mid year 16V, sorting out some electrical problems.

Bret928

Mine is a 16v Chris.

So I'll have a look tonight again when I can see everything better.

But again the tail lamp warning only happens when I have the lights on. So I would tend to think that I would see a light not working but I never thought to see if any where brighter than the others.

I'll let ya know what I find.

Alan

Bret - you only ever get warning while the lights are on - it can only see that the bulbs are consuming the wrong amount of power if they are on. The stop lights are a special case where the warning initiates on start-up & stays on until you activate them - seems this was supposed to be a motivation for you to test them right after start-up. Again - the actual testing only happens when the lights are on. I'd suggest replacing all the bulbs with a matched set (L/R) of the correct wattages.

In general the only monitored circuits are:

Brake/Stop lights (all 3 if you you have a central one)
Rear Markers & Rear Side Markers (together)

Turn Signals don't have the same kind of monitoring but will flash faster if a bulb blows... sort of secondary monitoring (...lost if you subsitute LED's)

Front markers, Front/side markers, headlights, foglights and aux headlights have no monitoring, neither do license plate lights or reversing lights.

Alan

Sharkdad

Did you do a search or check the owner's manual? Seems like I remember reading someplace this is normal. Just a thought.

Alan

Eh? I don't think so...

BIMMERMIKE

Play with the light switch and see if the "Tail Lamp" goes out or on. I had the same problem and turned out to be the switch itself. I cleaned sockets and replaced bulbs with no luck. Replaced light switch and no "Tail Lamp" light.

jheis

I think this may be one of those "electrical part of the ignition switch" gremlins. My car used to do it pretty regularly. Don't think I've seen it since I did the ignition switch thing.

James

JPTL

I think what Sharkdad's referring to is the brake warning light coming on at ignition/startup & staying on until the brakes are depressed:
Stop Lamp-
"The warning light comes on and goes out after depressing the brake pedal. If the light stays on, a bulb is defective."

Sharkdad

Thanks J.P., that's what I was referring to. In my GT, I get the same warning message for the "tail light" as posted above, but it goes off as soon as I touch the brake. It's done this since I got the car a few months ago. I took this for normal, based on what you referenced. If it's not, looks like I have the same problem as Bret.

Alan

No - that's the stop light (brake light) not tail light - that point was already discussed above. Sharkdad it is normal so you don't have an issue with your car - but that's not what's happening here...

I also don't think its related to the ignition switch - I don't see any way this can be... (though a stop light warning could be triggered by this).

I also don't really see how the light switch could affect this either.

I would not contemplate changing either of these to fix this if it were my car.. plenty of other things to investigate first (bulbs, grounds etc).

Alan