Does Exhaust brake activate brake lights?
I have a 2008 Monaco Diplomat and when the Exhaust Brake activates my brake lights don't come on. I mention this because in my 2005 Cayman the Exhaust Brake activated the motor home brake lights so th...
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Federal Motor Vehicle Safety Standards allow it to be set up either way. Whether your coach acts one way or the other is a function of the chassis maker. Tiffin Allegro Buses on a Freightliner chassis have the lights activate with the exhaust brake, those on a Tiffin designed Powerglide do not. Don't know about Spartans. I've had both a Freightliner and a Powerglide Bus and speak first hand. If your lights illuminate with the engine brake, a reprogram to the Engine Control Module can turn it off. It may or may not work the other way.
On our 2013 Bus on a Powerglide chassis, the brake lights do not illuminate with the engine brake. A trip to Alaska last summer showed many people coming up on the rig too fast when I was on the engine brake descending long grades. I asked Tiffin to reprogram the ECM to allow the brake lights to come on with the engine brake, and they accommodated me. However, when we tested it, the system worked like it should have, but with the first activation the Check Engine Light came on and would not reset. It turns out that when the ECM turns on the brake lights, it also sends a signal to the dash to illuminate a light on the dash showing the lights are on. On the Freightliner, this works fine. On the Powerglide, there is no dash light present, so when the computer tries to turn it on and cannot, it sends the Check Engine light. All these circuits are digital so an LED and a wire is not an option. I could probably design a mechanical system to come off the compression brake controller, but it seems like it's getting rather deep and no worth the effort.
On our 2013 Bus on a Powerglide chassis, the brake lights do not illuminate with the engine brake. A trip to Alaska last summer showed many people coming up on the rig too fast when I was on the engine brake descending long grades. I asked Tiffin to reprogram the ECM to allow the brake lights to come on with the engine brake, and they accommodated me. However, when we tested it, the system worked like it should have, but with the first activation the Check Engine Light came on and would not reset. It turns out that when the ECM turns on the brake lights, it also sends a signal to the dash to illuminate a light on the dash showing the lights are on. On the Freightliner, this works fine. On the Powerglide, there is no dash light present, so when the computer tries to turn it on and cannot, it sends the Check Engine light. All these circuits are digital so an LED and a wire is not an option. I could probably design a mechanical system to come off the compression brake controller, but it seems like it's getting rather deep and no worth the effort.
