The message "Check Brake Light Circuit" has been popping up on my 1997
M3. It happens sporadically. Upon visual inspection, there seems to be
nothing wrong: The brake lights behave correctly, no fuses are burned.
The message sometimes goes away when the ignition is turned off and back
on. Sometimes it persists.
I'd like to say that this is seasonal - I've seen it happens more often
when it is cold. But I can't confirm it. It seems to happen whenever the
hell it feels like it. I live in Florida, so this may not mean much anyway.
I took it to the dealer, of course the message refused to show then.
Mechanic grumbled something about brake pedal sensor, and $500 to
diagnose (!).
Anyone encounter this problem, and any advice?
Thanks!
t o n y
J Strickland - 07 Sep 2005 19:19 GMT
There is a switch that costs aobut $10 that causes this message. There is no
troubleshooting involved, and the failing switch is well known. It takes a
few minutes to get the cover off from over the pedals, then another few
minutes to get the switch off and the new one on.
With the uncomfortable contortions that it takes to work around the pedals,
it should take less than 1/2 hour to replace.
> The message "Check Brake Light Circuit" has been popping up on my 1997 M3.
> It happens sporadically. Upon visual inspection, there seems to be nothing
[quoted text clipped - 16 lines]
>
> t o n y
DP525 - 07 Sep 2005 21:55 GMT
Yes, brake light switch. It is actually two switches in one. One
operates the lights and the other is a diagnostic input to the LKM.
Dave Plowman (News) - 08 Sep 2005 17:41 GMT
> Yes, brake light switch. It is actually two switches in one. One
> operates the lights and the other is a diagnostic input to the LKM.
LKM?

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Kyle and Lori Greene - 08 Sep 2005 14:31 GMT
> The message "Check Brake Light Circuit" has been popping up on my 1997 M3.
> It happens sporadically. Upon visual inspection, there seems to be nothing
[quoted text clipped - 16 lines]
>
> t o n y
Like the others said it's the brake light switch behind the pedal. There
are two different switches that could be there, a 2-pin (pn 61 31 8 360 420)
or a 4-pin (pn 61 31 1 382 385). Check to see what you have before buying
the wrong one. Both can be had for $10-20 each.
https://www.autohausaz.com/catalog/lookup_parts.cfm?SubcategoryID=4720&VehicleID
=1013252&CFID=611151&CFToken=84282279
http://www.bavauto.com/shop.asp
$500 to diagnose this problem? Where did you take your car? I've been to
Reeve's in Tampa and All Pro in Ocala for electrical problems that I
couldn't do myself. Both are much more reasonable than that.
Kyle.
97 M3
98 740iL
Tony - 08 Sep 2005 16:28 GMT
>>The message "Check Brake Light Circuit" has been popping up on my 1997 M3.
>>It happens sporadically. Upon visual inspection, there seems to be nothing
[quoted text clipped - 33 lines]
> 97 M3
> 98 740iL
Thanks - very useful. The estimate was from the mechanic rep, at a BMW
dealer in Jacksonville.