Brake lights stuck on!

[trikey]

As the title, I have brake lights stuck on, wifes auto diesel, I changed pedal switch for three different ones (The last one from another auto) still no avail, tried two different LSM's too?

The only difference I can think of is the last switch came from an auto with cruise fitted, wifeys car is an auto without cruise...

Any ideas??

[David Lawrence]

As the title, I have brake lights stuck on, wifes auto diesel, I changed pedal switch for three different ones (The last one from another auto) still no avail, tried two different LSM's too?

The only difference I can think of is the last switch came from an auto with cruise fitted, wifeys car is an auto without cruise...

Any ideas??

did you change the holder as well as the switch? it could be that your new switches are sliding through the holder and not keeping in place properly.

[dissy1810]

Well mine work great ;) cheers andy. Do yours go out when you unplug the switch ? Have you rewired behind the dash properly

[trikey]

Well mine work great ;) cheers andy. Do yours go out when you unplug the switch ? Have you rewired behind the dash properly


They stay on Steve, regardless of switch plugged in or unplugged, yes, wires all connected properly behind dash...

Got me beat this one :shrug:

[dissy1810]

They stay on Steve, regardless of switch plugged in or unplugged, yes, wires all connected properly behind dash...

Got me beat this one :shrug:

With the switch unplugged mine didn't come on at all so I'd suggest you look at the back lights themselves and check the wiring on them it seems you may have a fault there maybe unplug them both and see if the high one works it's gotta be worth a try

[trikey]

With the switch unplugged mine didn't come on at all so I'd suggest you look at the back lights themselves and check the wiring on them it seems you may have a fault there maybe unplug them both and see if the high one works it's gotta be worth a try


Already tried Steve, like I say - stumped!!??

[Mike Noc]

Trikey does the high level brake light come on at the same time as well?

Mike

[Ros3]

Mine were doing this for a time there. So i reached up under the dash, moved back the cover on the switch and filled it with penatrating spray.. Hasent stuck since and that was about november when i did it..:)

[David Lawrence]

Mine were doing this for a time there. So i reached up under the dash, moved back the cover on the switch and filled it with penatrating spray.. Hasent stuck since and that was about november when i did it..:)

Are there 2 kinds of switch then? I had assumed your switch was the same as mine, a hall effect switch with no moving parts, nothing to lubricate. If the switch is too far away from the tang on the brake pedal it turns the lights on.

I think that your switch could be too far away. Try removing it from its holder and then physically holding the switch on top of the pedal so it is touching

[trikey]

Are there 2 kinds of switch then? I had assumed your switch was the same as mine, a hall effect switch with no moving parts, nothing to lubricate. If the switch is too far away from the tang on the brake pedal it turns the lights on.

I think that your switch could be too far away. Try removing it from its holder and then physically holding the switch on top of the pedal so it is touching


Yes hall effect switch, tried removing it then making the circuit, lights illuminate (High level one too) even when switch is just dangling on the wires with nothing making contact.

[Mike Noc]

Yes hall effect switch, tried removing it then making the circuit, lights illuminate (High level one too) even when switch is just dangling on the wires with nothing making contact.

The lights should be on if the switch is dangling - they go off when it detects the brake pedal. As mentioned try holding it against the pedal.

Mike

[trikey]

The lights should be on if the switch is dangling - they go off when it detects the brake pedal. As mentioned try holding it against the pedal.

Mike


Lol, sorry Mike, I knew what I meant! :p:

The lights stay on regardless of contact made or unmade.

[Mike Noc]

Thought that might have been the case. :D

If you've changed the LSM and still have the same fault then all I can suggest is tracing the cable back from the switch plug and checking for continuity.


Mike

[trikey]

Switch totally unplugged - lights still on, is this normal?

[Mike Noc]

Never tried it but I would have thought so as the signal from the switch keeps the brake lights off.


Mike

[dissy1810]

Switch totally unplugged - lights still on, is this normal?

Like I said earlier with it unplugged on mine no lights at all

[trikey]

Yes Steve,

mine are still bloomin stuck on, tried everything now..

:shrug:

[David Lawrence]

Yes Steve,

mine are still bloomin stuck on, tried everything now..

:shrug:

tried disconnecting the switch then do a battery reset?

[trikey]

New switc bought, battery reset done..










Still stuck on!!!!!

[David Lawrence]

New switc bought, battery reset done..










Still stuck on!!!!!

Are your plenums clear? Could water be upsetting the electrics? Clutching at straws now !


Not got a towbar have you? Loose wiring around those have been blamed for this kind of thing as well.

[trikey]

Are your plenums clear? Could water be upsetting the electrics? Clutching at straws now !


Yep plenums dry, looks like its trace wires time!

[Trophy Blue Tourer]

Not got a towbar have you? Loose wiring around those have been blamed for this kind of thing as well.

As above!! It has been known for a faulty/damaged or just plain wet towbar socket to short or the cheaper type of by-pass relay to "back feed" the brake light wiring and cause this sort of fault!!:shrug:

HTH?

Andy

[Ros3]

Are there 2 kinds of switch then? I had assumed your switch was the same as mine, a hall effect switch with no moving parts, nothing to lubricate. If the switch is too far away from the tang on the brake pedal it turns the lights on.

I think that your switch could be too far away. Try removing it from its holder and then physically holding the switch on top of the pedal so it is touching


I dont know mate. All i know is that i moved back the rubber sleave and filled it up with the spray. It's worked fine ever since.?.:shrug:

[David Lawrence]

I dont know mate. All i know is that i mover back the rubber sleave and filled it up with the spray. It's worked fine ever since.?.:shrug:

Here is my switch, as you see, no rubber sleeve, Is yours different? 20051

[Ros3]

Here is my switch, as you see, no rubber sleeve, Is yours different? 20051


Well i couldent actually see the part i was reaching up to as i'm quite big and couldent get right up under the dash, i was working by feel alone. But no nothing like that mate. What i found was like a rubber sleave, facing forward and atached about 3/4 of the way up the back of the pedal. I moved it back and filled it up them worked it back into place. Has been fine ever since, and mine were stuck on almost all the time.. :shrug:

[David Lawrence]

Well i couldent actually see the part i was reaching up to as i'm quite big and couldent get right up under the dash, i was working by feel alone. But no nothing like that mate. What i found was like a rubber sleave, facing forward and atached about 3/4 of the way up the back of the pedal. I moved it back and filled it up them worked it back into place. Has been fine ever since, and mine were stuck on almost all the time.. :shrug:



You are describing the bellows on the pedal push rod? (Below letter B)

20052

Was your entire pedal sticking down a bit? That's the clutch push rod is it? Is the brakes the same? I know that some people found stuffing that with grease stopped it clicking. But its not connected electrically.

[Ros3]

Emm i'm not sure mate.. All i know is that's what i did and it's been fine ever since. No problem with the light's.. :shrug:

[David Lawrence]

Emm i'm not sure mate.. All i know is that's what i did and it's been fine ever since. No problem with the light's.. :shrug:



Sounds like your fault must have been a sticking pedal or push rod which kept the brakes pressed a bit, but Trikey's has an electrical problem it seems.

[Ros3]

Must have been.. Well either way good luck with it.. :)

[trikey]

No towbar :)

[David Lawrence]

No towbar :)


Water leaking through the rear light seals settling on the wires?

[samurai]

Daft question when your checking the brakelights you havent got the sidelights on , if you have , remove the bulbs one by one , in case the filaments have fused , if not then the brakelight wire is picking up a feed , ive checked a diagram ive got and it appears to go through a module light unit , disconnect it see what happens , i think the wire is green/brown , ill check later to see if ive been of help .:confused:

[trikey]

Water leaking through the rear light seals settling on the wires?


Nope! Does the same with the rear units unplugged and only the hi level light on.

[trikey]

Daft question when your checking the brakelights you havent got the sidelights on , if you have , remove the bulbs one by one , in case the filaments have fused , if not then the brakelight wire is picking up a feed , ive checked a diagram ive got and it appears to go through a module light unit , disconnect it see what happens , i think the wire is green/brown , ill check later to see if ive been of help .:confused:


No sidelights (I have tried all combinations of lights on and off) will try removing each bulb in turn next (though all bulbs work fine)

[David Lawrence]

Water leaking through the rear light seals settling on the wires?

Any chance you could disconnect the brake switch and check the wires coming from it if the wire on pin 4 is somehow shorting to ground? If it is that would tell you there is a short somewhere between the brake switch and the light switch module. That should be the Green/purple wire.

From my understanding of the circuit diagram all 3 brake lights come from different outputs of the LSM (pins 5, 10 and 16) and as they are all 3 lit up, if the input to the module is not grounded with a short then it would suggest the LSM is faulty.

Very unlikely that a wiring fault between the LSM and the light bulbs would simultaneously arise on 3 separate wires so I'd start looking there.


Hmm, now I'm wondering if the pins in the connector on the switch might be bent over? shorting against each other?

[Moodster020]

Mine were doing this for a time there. So i reached up under the dash, moved back the cover on the switch and filled it with penatrating spray.. Hasent stuck since and that was about november when i did it..:)
I had the same problem as well, did the above too & now working fine.

Use one with a long nozzle so you can get the lube right up in there :p:

[trikey]

Any chance you could disconnect the brake switch and check the wires coming from it if the wire on pin 4 is somehow shorting to ground? If it is that would tell you there is a short somewhere between the brake switch and the light switch module. That should be the Green/purple wire.



From my understanding of the circuit diagram all 3 brake lights come from different outputs of the LSM (pins 5, 10 and 16) and as they are all 3 lit up, if the input to the module is not grounded with a short then it would suggest the LSM is faulty.



Very unlikely that a wiring fault between the LSM and the light bulbs would simultaneously arise on 3 separate wires so I'd start looking there.





Hmm, now I'm wondering if the pins in the connector on the switch might be bent over? shorting against each other?


Thanks for the info David, I will try when I'm back home Monday, fingers crossed!

[David Lawrence]

Thanks for the info David, I will try when I'm back home Monday, fingers crossed!


Another point of curiosity, is your cruise control working? If it is then that tells you your switch is fine as that is the second output from the brake switch

[trikey]

Another point of curiosity, is your cruise control working? If it is then that tells you your switch is fine as that is the second output from the brake switch


Don't have cruise fitted David, I will be fitting it shortly though if I cannot get to the bottom of the lights on situation, as you say it will show up on T4 if it has criuse ;)

[David Lawrence]

Don't have cruise fitted David, I will be fitting it shortly though if I cannot get to the bottom of the lights on situation, as you say it will show up on T4 if it has criuse ;)

By putting a resistance checker across the terminals of the switch with it removed, then sticking it to a piece of steel or iron you should see the resistance change. This will confirm if the switch is working. If i remember correctly the resistance is lowest when it is stuck on the pedal and goes up when the pedal is pressed. (Switch moved away from the pedal)

The numbers on the switch are extremely small but the 2 sets of contacts are between pins 1 and 3 and then 2 and 4, so just test both alternate pairs and you wont need to worry about reading the numbers. The point is you need to see the resistance change between metal on and metal off.

I cant tell you exactly what the resistance should be because i only have a failed switch to check but it measured 1M ohm with it stuck to metal, and Open circuit with the metal removed, but as I say that is a failed switch which gave me......well, lights on all the time, but it did work when the weather was warm.

You need 3 or 4 hands to make all the contacts and manipulate a piece of metal at the same time.

[trikey]

Thanks David, I will try that, don't think it is the switch as I have fitted four different ones now! (And one new one!) Pretty sure its a wiring fault somewhere...

[trikey]

Well once again marinabrian's advice proved to be correct, a missing fuse (Number 13) from the fusebox in the passenger footwell, replaced with a 5A fuse and hey presto, brake lights extinguished.

:bowdown: Nice one Bri :bowdown:

[BIG LEK]

Well once again marinabrian's advice proved to be correct, a missing fuse (Number 13) from the fusebox in the passenger footwell, replaced with a 5A fuse and hey presto, brake lights extinguished.

:bowdown: Nice one Bri :bowdown: All that for the sake of a fuse:shrug: andy we would be lost with out Bri:D:D;)