Originally Posted by n0ukf
On my '97 Adventurer 34 (Chevy P30 chassis) sometimes while driving I notice the autopark light is faintly (very short on period) blinking every second or two. This has the additional effect of slightly dimming all the other chassis lights during that blink. When in Park and the key is on, the light is solidly on indicating that the brake is engaged. The foot brake also turns this light on, though right now neither one securely applies the brake, they need to be adjusted or shoes replaced (but I can't yet get the drum nuts off).
Does anyone have an idea what is going on here?
My 2002 Sightseer was doing the same thing. Mine was blinking on and off about every 20 seconds for just a fraction of a second. Turned out to be a solenoid valve in the autopark system that was leaking down. When the pressure leaks down even a little bit, the pump will start, the light will come on until the pressure builds back up, then the light goes off. The pump only has to run for a fraction of a second to repressurize. Actually, mine pumped up so quickly, it sounded like a click instead of sounding like a pump running.
To check to see if you have the same problem I did, try the following procedure. Park on level ground where the motorhome won't roll and chock the tires. Turn the ignition on, but don't start the engine. Pull the shift lever out of park. You should hear the autopart pump motor run for about four seconds as the brake is released (and the parking brake light will go out), then wait to see if you hear the parking brake pump run for a fraction of a second while the autopark light blinks on and off.
If so, your solenoid valve is probably bad. It can be removed and cleaned, but that's not a sure fix. It's better to replace it. That's what I did. Part number and description: AC Delco 15149862 GM Original Equipment Parking Brake Pressure Solenoid Valve Assembly. $135.00 was the best price I found at Amazon.