Brake Light Switches - what is the difference?

[Airborneduck]

I have a 1995 E34 540i V8 Auto, RHD. I decided to change the brake light switch (located in the passenger footwell on the left hand side of the car, on the opposite side to the pedals) to try to cure an incorrect check control warning "brake light-lic plate light-dip beam". The replacement switch supplied by my BMW dealer is part number 61318360417. However, the original switch I found on the car, from when it was first built, is part number 61318356527 and has a circuit board and heat sink mounted around it, and it costs a couple times more than the 417 switch. So, which one should I use as a replacement? The parts diagrams are not helpful in making a decision - the diagram for the RHD drive car lists the cheaper 417 switch for the passenger footwell, whereas the parts diagram for the LHD car (with the brake switch above the pedals) shows the expensive 527 switch, contrary to what I found on my car. I spoke to my friendly BMW dealer's parts department and they said thay always supplied the cheaper 417 switch, and had never heard of the expensive 527 switch. I know that the cheaper switch is purely mechanical, and that the expensive switch is electronic, but apart from that does anyone know why these two switches are listed and what the differences are and which is the correct one to use? I believe the expensive switch is also used on the 740i. Its all definitely a dark art. I long for the days when all you had to do was look around the car to see if a bulb had blown, and not have a mindless computer give you the wrong info every time you drive at night.

[shogun]

I only could check on realoem.
61318360417 STOP LIGHT SWITCH 4-POLIG/MECH. From:03/01/1994 To:- Supersedes: 61311382385(03/01/1988 — 12/28/1994)
Part 61318360417 was found on the following vehicles:
•3' E30   (04/1985 — 05/1993)
•3' E36   (11/1989 — 10/1999)
•5' E34   (03/1987 — 06/1996)
•7' E32   (10/1985 — 04/1994)
•8' E31   (07/1989 — 10/1996)
•Z3 E36   (12/1994 — 06/2002)

61318356527 STOP LIGHT SWITCH 4-POLIG/ELO From:04/01/1992 To:-
Part 61318356527 was found on the following vehicles:
•5' E34   (03/1992 — 06/1996)
•7' E32   (11/1986 — 04/1994)
•8' E31   (07/1989 — 05/1999)

61318356527

STOP LIGHT SWITCH

4-POLIG/ELO
From:04/01/1992To:-Weight:0.052 kgPrice:$144.29
Part 61318356527 was found on the following E34 vehicles:•5' E34, 530i, Sedan, M60, MANUAL, EUR, (HE11) : PEDALS/STOP LIGHT SWITCH
•5' E34, 530i, Sedan, M60, MANUAL, EUR, (HE12) : PEDALS/STOP LIGHT SWITCH
•5' E34, 530i, Sedan, M60, AUTO, EUR, (HE21) : PEDALS/STOP LIGHT SWITCH
•5' E34, 530i, Sedan, M60, AUTO, EUR, (HE22) : PEDALS/STOP LIGHT SWITCH
•5' E34, 530i, Touring, M60, MANUAL, EUR, (HK11) : PEDALS/STOP LIGHT SWITCH
•5' E34, 530i, Touring, M60, MANUAL, EUR, (HK12) : PEDALS/STOP LIGHT SWITCH
•5' E34, 530i, Touring, M60, AUTO, EUR, (HK21) : PEDALS/STOP LIGHT SWITCH
•5' E34, 530i, Touring, M60, AUTO, EUR, (HK22) : PEDALS/STOP LIGHT SWITCH
•5' E34, 540i, Sedan, M60, MANUAL, EUR, (HE51) : PEDALS/STOP LIGHT SWITCH
•5' E34, 540i, Sedan, M60, MANUAL, EUR, (HE52) : PEDALS/STOP LIGHT SWITCH
•5' E34, 540i, Sedan, M60, AUTO, EUR, (HE61) : PEDALS/STOP LIGHT SWITCH
•5' E34, 540i, Sedan, M60, AUTO, EUR, (HE62) : PEDALS/STOP LIGHT SWITCH
•5' E34, 540i, Touring, M60, MANUAL, EUR, (HK31) : PEDALS/STOP LIGHT SWITCH
•5' E34, 540i, Touring, M60, MANUAL, EUR, (HK32) : PEDALS/STOP LIGHT SWITCH
•5' E34, 540i, Touring, M60, AUTO, EUR, (HK41) : PEDALS/STOP LIGHT SWITCH
•5' E34, 540i, Touring, M60, AUTO, EUR, (HK42) : PEDALS/STOP LIGHT SWITCH
http://www.realoem.com/bmw/enUS/partxref?q=61318356527&series=E34

http://www.realoem.com/bmw/enUS/partxref?q=61318360417&series=E34

What does realoem show when you search with your VIN?

[Airborneduck]

My RHD HE62 car was built in March 1995 and entering its VIN into Realoem shows the cheaper 417 switch on the foot controls/deflection rod drawing (which is the correct drawing for my RHD car, and is where my switch is actually mounted on the opposite side to the pedals), but my car in fact originally had the expensive switch factory mounted in that location. However, Realoem shows the expensive 527 switch on the foot pedals drawing. I have not yet seen the expensive switch mentioned or shown on the internet on any forum; all the brake light switches I've seen on forums are mounted over the pedals on LHD cars and are the cheaper 417 switch. I do appreciate your help Shogun. I think its going to possibly remain a mystery.

[632 Regal]

No there are 2 different switches on both the USi cars and others. One is just the 2 terminal and the other is a 4 terminal switch. What you mention is a circuit with a circuit board which might be contained in either of the ones I mention could be wrong on your RHD vehicle. You need to do a bit more research so we can figure this out.

[shogun]

As far as I remember: 2 for cars without check control, 4 for cars with.
On the 4 pin unit: 2 pins are for the actual circuit itself and the other 2 pins are for the Check control system.

These are two different warning things.

"Brake Circuit Failure" is almost certainly the switch on your brake pedal.

"Brake Light Failure" means one or more of your brake lights is not working.

[Airborneduck]

As far as I remember: 2 for cars without check control, 4 for cars with.
On the 4 pin unit: 2 pins are for the actual circuit itself and the other 2 pins are for the Check control system.

These are two different warning things.

"Brake Circuit Failure" is almost certainly the switch on your brake pedal.

"Brake Light Failure" means one or more of your brake lights is not working.

The connector is a 4 pin, as my car has check control. The photos show the expensive 527 switch both on the car and removed from the car. The check control message on my car is 'brake light-lic plate light-dip beam'. All the rear lights work correctly and I have tested the check control by pressing in the test button on the instrument cluster and it replies 'check control OK'. I was wondering if the expensive 527 switch might be a MOSFET switch which requires very little current to turn on while delivering a much higher current to a load. This would reduce arcing across the contacts and prolong the life of the switch. Just a guess on my part and it might not be a MOSFET at all.

[632 Regal]

I have never seen a switch like that one. Seems that this one checks more things than just check control which could be the difference. Never saw this
"brake light-lic plate light-dip beam" warning just the standard 'check control' or 'brake light circuit'. Did you try the 417 switch yet?

[shogun]

That is all standard warning thru the check control
brake light circuit is priority 1 = immediately displayed followed by a gong and flashing reminder symbols. If more than one fault occurs at once, the displays are shown in succession. These displays cannot be cancelled with the CC ket (right button).
lic plate is priority 2 = display appears when ignition key is in position 2 (if priority 1 faults occur, these are autoatically superimposed). After the display has gone out, the reminder symbols remain. If a plus sign appears, this means that there are further displays which should be called up by pressing the CC button.
dip beam is priority 2

'check control OK' means means only that the display is o.k., but not the check control module. That is clearly mentioned in the owners handbook.
As all lights are o.k. according to your checking, then in my opinion the problem is the check control module. This happens quite often that they get cracked solder joints and then even sometimes display items which the car does not have.
In that case you have to resolder the check control module, see here a good info in German language with enough pics, so that you even do not need to translate the text, see especially the items on page 8 + 9
http://www.e34-welt.de/tips_tricks/Reparaturanleitung%20CCM%20e34%20e32.pdf
Also here they mention as possible causes for strange warnings in the check control, although all parts work fine:
- headlight aim motors (on EURO models mainly), they can cause a lot of faulse warnings when getting older)
-contact at brake pedal switch
-wrong taillights from an E34 without check control, installed in an E34 with check control
-defective check control module
-or still a part defective?

[Airborneduck]

I much appreciate both your help. The 517 switch has made no difference, the warning lights still come up. I'll have a look at the CCM solder joints in due course. Both the headlamp aim motors are working fine, but its interesting Shogun that you mention the taillights. A few years ago I changed both the outer rear lamp units for 'clear' ones and there were no problems for a long while afterwards. I didn't realise that there were different taillights for E34s with and without check control - what is the difference, is there a different wiring circuit for example? I have sent an email to BMW customer service and they said their tech dept would get back to me. I'll post their reply when I get it - should be interesting?

[shogun]

In the repair info for the CCM there is nothing addition mentioned about differences between taillight with/without check control. But I checked on some German forums, here on an E36 forum they say:
Rückleuchten für Fahrzeuge mit Check-Control haben am Anschlußstecker einen Pin mehr als Rueckleuchten (RL) für Fahrzeuge ohne CC. Der zusätzliche Pin ist vorhanden, weil bei diesen Rückleuchten beide Glühlampen für das Schlußlicht separat vom CC-Modul eingespeist werden, bei Fahrzeugen ohne CC ist nur eine gemeinsame Zuleitung vorhanden. Die Anschlüsse für Blinker, Bremslicht, NSL und Rückfahrscheinwerfer sind identisch. (Im Zweifelsfalle vergleiche die Anzahl und Position der Pins mit den originalen Rückleuchten.) Es gibt dann noch Rückleuchten, die für Fahrzeuge mit und ohne CC geeignet sind. Diese RL sind im Prinzip RL für Fahrzeuge mit CC (haben also den zusätzlichen Pin) und können durch einsetzen/herausnehmen einer Brücke zwischen den Leitungen der beiden Rückleuchten umgebaut werden. Durch den Einbau falscher Rückleuchten kann nichts kaputt gehen! (Auch, wenn Du nur eines eingebaut hast.) Baut man Leuchten mit CC in Fahrzeuge ohne CC ein, leuchtet je Seite nur eine der beiden Rückleuchten, baut man Leuchten ohne CC in Fahrzeuge mit CC ein, so leuchten beide Lampen aber es erscheint eine Fehlermeldung im CC. Daher hat entweder der Defekt des Blinkrelais nichts mit der Rückleuchte zu tun, oder aber an der Leuchte ist ein Defekt vorhanden.

Brief translation: taillights with check control have at the plug 1 pin more than cars without check control. Use google translate
http://www.motor-talk.de/forum/woran-erkenne-ich-check-control-rueckleuchten-bzw-warum-t1098732.html

Another find: My car is a 96 316i so I didnt have the CHECK CONTROL computer and module fitted.
When fitting the new M3 rear lights, I found that the break lights were not working properly and there were other slight problems. Thats when I realised the PINS were slightly different on the new lights.

First step is to bridge pins 4 and 8 on both sets of lights. The easiest and best way to do this, with an easy way to reverse the mod is to solder the 2 pins together. DO NOT actually solder the pins, bridge a short bit of wire from one panel to the other. The design of these lights is in such a way that there is no wiring, just sheets of metal.

The Second step is to connect a peice of wire to the plug on the right hand light(offside)(drivers). The wire you must connect is the one corresponding to PIN 3. You will see on the light that there is no PIN, which is why you must use the plug from the car. You must then connect the wire from PIN 3 of the plug to PIN 2 of the lights. The way I did this was to solder a wire to the panel corresponding to PIN on the light, then use a crimped connector to connect to the wire coming off PIN 3 of the plug.

Sounds complicating? Its not really, just remember which pins need to be bridged.

The pics below will show you exactly what mod you need to do:

1st step. Bridge pins 4 and 8 on BOTH lights so its like below:

2nd step. Solder wire to pin 2 panel of the Offside light(drivers side):

3rd step. Modify the wiring on the car, I connected a scotch plug and another wire to the wire for PIN 3 like below:

4th step. Crimp connectors onto each wire and connect, making an easy way to reverse the mod. (YELLOW wire from lights, RED wire from PIN 3 scoth plug. Alternative methods can be used obviously:
http://www.bmw-forum.de/viewtopic.php?p=337870&sid=92228aaa29c710ba367325295baca04f

Edit, here in English with pics from E36
Convert-rear-lights-from-non-check-control-to-check-control-DIY
http://www.bimmerforums.com/forum/showthread.php?1600722-E36-Convert-rear-lights-from-non-check-control-to-check-control-DIY

[632 Regal]

Aftermarket tail lights... Make sure all the solder connections and the bulb socket connections are contacting properly. When I had clears I would always have intermittant issues with them either not working or the same warning you are getting. On mine the contacts to the housing were not 100% correct and twisting them less than full would temporarily fix the problem.

The car I have now has stock lights and I get the brake light circuit warning occasionally. This was remedied with a new switch but that one short circuited and I put the stock one back in. I have a spare "new" aftermarket one I am saving for emergency.

[Airborneduck]

Thanks Shogun, that's interesting. I'll have a look at the rear lights to see if they're CC or non-CC. In the meantime, I received a reply from BMW Customer Service. They told me that the correct brake light switch for my car is the original expensive one, 61318356527. They did not give a reason so I asked them for one and am awaiting another reply. I'll fit a new 527 switch and see what happens. I have pulled most of what is left of my hair out already.

[whiskychaser]

Here is a theory and it rather depends on where you are. If your car was built without a third brake light (as mine was) and you bought the kit to add one, I'd suggest that check control would throw a fault. But there is nothing in the instructions for adding the third light which mentions changing the switch. Perhaps the circuit board in your brake switch is intended to cheat check control into thinking there are still only two lights. Plausible?

[Airborneduck]

Yes certainly plausible Whiskeychaser. My car doesn't have the third brake light and still only has two. I'm still waiting on BMW customer service to get back to me as to why there is an electronic brake light switch.

I checked the electrical socket on my aftermarket tail lights and they have four pins and exactly match the electrical plug in the wiring loom so no need to do any work there. In any case the aftermarket tail lights worked for many years before the check control went 'ping'.

One thing I did notice that I forgot to mention - years ago, when everything worked correctly and the check control behaved, whenever I braked I noticed a distinct clicking sound from the electronic brake switch, and the clicking stopped around the time that the check control went wonky. I'll be fitting the replacement electronic 527 switch soon (should arrive today) and will report back as to whether the check control is still pinging.