Hello…2005 gem e4, 2400 miles—brake lights come on, don’t turn off. I’ve lifted up on the brake pedal, disconnected the brake pedal contact switch wires, etc. New pressure switch installed at the brakes fluid reservoir. Only turning off the master switch turns off the brake lights. Thoughts ?
Can you give us a little history?
How long have you had this car?
Did it just recently start doing this?
What have you done to the car lately around the time this started acting up?
(any wiring changes, replaced the tail lights, stuff like that)
You said you replaced the pressure switch. The one in the casting? or up at the plastic reservoir?
What color is the GEM?
Hi! I’ve had the cart for 2 years. The Brake light on Issue was addressed by the dealer who did a brake inspection, replacing the brake pressure switch for 01362 that goes into the reservoir and replaced the batteries. The issue came back shortly there after. I just replaced the brake pressure switch again hoping that would help. It did not.
Hi…the gem is white in color.
Hmmm… try pulling a couple fuses and see if it is coming in from an odd path.
Next, start moving around a few wire bundles and see if you find something that is not appropriate. You may need someone back of the car watching for a flicker of any sort.
Is there anything else acting strange on the car? (Turn signals? Headlights?) What does it do when turn signal flipped one way or the other?
I’ll have a look at the diagram to maybe trace this path out.
I also have a 2005 e4 and had the same issue. Can we correctly assume when you say dealer and you replaced pressure switch on reservoir you are meaning pressure switch on side of master cylinder and not actually in reservoir? Also, if you pull leads from said pressure switch there is no change in light status?
Correct, the metal switch pressure switch was replaced, twice.
Did not fix the issue, nor tun off the brake lights when the wires pulled.
How did you fix the issue?
Hi…yes. The switch seems to be operating. The brakes come on and don’t turn off, even when the pressure switch is disconnected.
Pressure switch fixed mine.
Sorry not more help.
When the pressure switch was removed, did fluid come out? Surprisingly it did not on mine, except for a few drops.
Interesting observation. A bit of fluid might come out, but then maybe not. If you pumped the brake for sure it would.
But then you should have confirmed it was NOT the switch when you unplugged the wires from the (metal based) switch and the lights were still on. <-correct? (or did they go off)
You say the switch seems to be operating. How exactly did you test it?
Did you try unplugging the fuses (one at a time) to see where the power might be coming from?
What happens to the tail lights when you turn on the headlights?
What happens when you flip on a turn signal?
Yes some fluid, more than drops but something like a trickle.
Following up on @AssyRequired questioning. When you turn off the key, the 72v to 12v converter should shortly power down as well and stop supplying 12vdc to all accessories. Sounds like thats not happening either?
the accessories turn off with the key, but the break lights stay on.
Brake lights activate with pedal push, and do not deactivate.
Try pulling up on brake pedal with your toe, mine does this occasionally. Under the dash there are two contact switches for brake light and one for brake failure. You need to adjust the switch.
(This is for a 199-2004, yours maybe slightly different).
Thanks, but pulling up does not turn off the brake lights, nor does disconnecting the switch electrical leads, sadly.
What I find interesting in your comment is that you say it comes ON with a brake press, but doesn’t go off when released. So it goes off somehow, sometime, eventually? Like just sitting? <- this may be an important clue if correct. After an overnight sit, check if it is indeed off. (I am working on a theory)
What switch are you pulling wires off and still getting light? (the metal can pressure switch on the Brake master?)
I think what Reddevil is saying is that there are two more
(mechanical) switches on the top of the brake pedal arm/assembly. You should have a look.
I will have a look at mine tomorrow and see if it has those switches, and see if they are related to the brake lights. I saw in the manual there might be one, but I assumed it was related to regen.
EDIT: I just looked on my 2009 and it has no other switches anywhere near the brake pedal assembly. I checked both sides of the firewall. It looks like they may have changed things after 2004? (your snip shows wiring for 99~04)
Thanks, I haven’t had any experience with the Gen 2 version, body looks identical but I have read here mechanisms had been improved. Sounds like a trip to the service manuals for that version is in order.
Sorry for leading you astray @mlm!
Thanks for helping! The only way the brake lights turn off is via the master switch. Even disconnecting the brake pedal plunger switch does nothing to turn the brakes on (they go on even with the switch disconnected) or off as they stay when the switch is disconnected.