j.kenzie@sbcglobal.net

CHMSL = Center High Mount Stop Light, pronounced CHIM sel.

Hi guys,
When I replaced my brake lights with LED's, I found I my remote starter (RS) would quickly start my car, but then it would die. After checking, I found that my brake lights were on very dimly whenever my ignition was on. I was getting 8 volts at my brake light switch, even with the pedal not depressed. This was telling the RS brain the brake pedal was depressed and to kill the engine.
Anyway, I went back to an incandescent CHMSL bulb, and now everything works fine.
BTW the RS/keylss entry is a huge convenience, so please hold the flames.

Message is that besides the cruise control brain, any RS brain also needs a proper brake switch input in order to function. (I'm sure my CC was not working either, but didn't try it.)
Good luck,
Dave

davek9

I'm guessing that you didn't by-pass the LAMP Controller, and also wire the brakes lights directly from the Brake light switch at the peddle?
The voltage you detected was the Lamp sensing circuit looking for a bulb

j.kenzie@sbcglobal.net

I did wire directly to the brake pedal switch. However, by only changing the CHMSL bulb back to incandescent, no other rewiring, the problem was solved. I never saw a stop light warning light either way. You may be right. I never considered the bulb warning system.
Thanks,
Dave

davek9

NP, never mind.
Dave K

Also the Lamp controller does monitor the Center Hi mounted too via one of the Brake Light circuits, the Right one IIRC, in later years it had it's own.

j.kenzie@sbcglobal.net

CHSML = Center High Mount Stop Light, pronounced CHIM sel.
Sorry, I thought it was common usage. My bad, and first post edited with definition.
Dave

MainePorsche

I have LEDs along with the Controller bypassed, but having the one incandescent up top is necessary for cruise control function for the filament acts as a ground. Maybe the RS needs this too.

j.kenzie@sbcglobal.net

I agree. I'm sure a resistor + LED could be made to work also.
Dave

Ed Scherer

You might have already seen it, but I did quite a bit of digging into the CC / brake circuitry when I was looking for (and developed) a solid-state solution for the "all LED brake lights breaks the cruise control" problem. Without going into a lot of detail here, I'll just say that the best, safest solution is a 6 Ω resistor in parallel with the brake lights.

Alan

It's not the lamp controller - wrt this behaviour it is completely passive. It is solely related to the cruise brain expecting a low impedance filament to ground. So indeed the ballast resistor is your best bet. You can mount it under the sunroof motor cover to the inner roof skin for good power dissipation - it will get very hot.

Alan

j.kenzie@sbcglobal.net

Like I said. One incandescent bulb put back in solved the problem. I kept the old ones in a box.
Dave

MainePorsche

I think this is a better remedy than a hot resistor somewhere in the vehicle.