The Diesel Stop banner

1 - 8 of 8 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter #1 (Edited)
2001 E-350
Engine ON the brake lights stay on all the time. (driving conditions)
Engine OFF but ignition in RUN brake lights off but work when depressed.
Engine OFF ignition OFF brake lights work when depressed only.
Engine OFF ignition ACC. brake lights work when depressed only.

kind of odd.. every key position they work fine... when engine is running lighst stay lit!!! HELP!!!:jester:
 

·
Premium Member
Joined
·
1,446 Posts
Could it be the brake light switch is adjusted with no clearance? And either the vibration of the engine is enough to connect it, or the vacuum canister pulls the pedal down enough to turn on the brake lights.

Mike
 

·
Registered
Joined
·
880 Posts
Do you have a trailer brake controller? I fault in the controller can feed back into brake light circuit.

It's also possible for the trailer brake controller wires to be smashed by the parking brake, and short together (this one happened to me).
 

·
Registered
Joined
·
5,313 Posts
measure brake pedal height from a very well identified place on floor and then start engine and check that height again.
I think the E's have vaccum booster for brakes.
Last, Pull the check valve out of booster and then start engine and check the height one more time.
My suspicion is brake booster issue.
The regulator valve on the pushrod into back of booster controls shutting off vent and filling back side of diaphragm chamber with vacuum to turn off assist.
If the regulator fails then it can let some vent air in back side and the pedal will go down a little (or a lot in some failures) and the brake light switch would be triggered.
If this is the case another symptom would be hard brake pedal before engine is started. Brake boosters usually hold the vacuum for a long time with engine off and will have normal pedal feel for one brake apply with engine off even days after engine was last run.
 

·
Registered
Joined
·
6,680 Posts
might want to take a look at your grounds, when you get really wacky behavior they are often the culprit. the power proportionally takes the easiest path to ground, and if that's through a lamp then so be it.
 

·
Registered
Joined
·
6 Posts
Discussion Starter #6
The Vacuum compressor failed which seemed to be causing the issue. I changed it and tested the brake lights and the seemed to be working fine. When I tap the brakes they work fine. When I hold the pedal down they stay illuminated. Regulater issue maybe. NE HELP??? -MIKE:jester:
 

·
Registered
Joined
·
1,927 Posts
Do you have a Viper alarm or other remote start alarm system?

My running lights & Brake lights stay on when the remote start is on, and I have read
some installed the systems wrong and this may happen.

I have a Viper system BTW.
 

·
Registered
Joined
·
1 Posts
2001 E-350
Engine ON the brake lights stay on all the time. (driving conditions)
Engine OFF but ignition in RUN brake lights off but work when depressed.
Engine OFF ignition OFF brake lights work when depressed only.
Engine OFF ignition ACC. brake lights work when depressed only.

kind of odd.. every key position they work fine... when engine is running lighst stay lit!!! HELP!!!:jester:
2001 E-350
Engine ON the brake lights stay on all the time. (driving conditions)
Engine OFF but ignition in RUN brake lights off but work when depressed.
Engine OFF ignition OFF brake lights work when depressed only.
Engine OFF ignition ACC. brake lights work when depressed only.

kind of odd.. every key position they work fine... when engine is running lighst stay lit!!! HELP!!!:jester:
Did you ever figure out what the problem was? Im having the same with my E250.
 
1 - 8 of 8 Posts
Top