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Since I've owned the car the reverse lights have not worked and neither has the cruise control.

I'd like to have both of these operating again.

Reverse Lights:
Was given the CC-ID: 117
Left reverse bulb out. I swapped both bulb holders and bulbs. It's not the bulbs or anything else. When checking voltage I only get .03 volts for the reverse voltage when in gear.

The purple and black cable must have a bad side somewhere grounding out. I have repaired the fire loom that goes from the trunk to the car and soldered multiple wires including the brown ground wire. I fear the wire for the reverse lights is deep in the car where I could not see the part that is causing the problem.
Since both reverse lights are out it must be past the whole trunk entirely.

I have reset the FRM for the reset counter with tool32 and still the same voltage.

Clutch switch works and has been tested.
Fuses all good.
This leads me to the next problem


Cruise Control:
No error at all on the BC or INPA
When I try to click the cruise on or even do anything with the stalk it is in "just for looks mode".
I've been trying to figure out how to test the stalk in INPA to see if the car is even recognizing it.
The brake pedal is not being depressed either; the switch is good.

What makes this even more weird is usually putting the mirror toggle to the left usually tilts the right mirror down; it does not go. Is that also wired with the reverse lights?

If anyone has any idea to what is going on here or any fixes or help please comment. If someone can successfully help me get these back I will PayPal $$$.



TL;DR
Reverse lights out; cruise control won't work
All fuses good; switches good.
Help fix
 

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Since I've owned the car the reverse lights have not worked and neither has the cruise control. I'd like to have both of these operating again.

Reverse Lights:
Was given the CC-ID: 117
Left reverse bulb out. I swapped both bulb holders and bulbs...When checking voltage I only get .03 volts for the reverse voltage when in gear...Clutch switch works and has been tested.
Fuses all good.
Since Cruise & Reversing Lights are unrelated, and you need the latter to pass safety inspection, I'm addressing that first:

Here is TIS circuit diagram for reversing lights circuit:
https://www.newtis.info/tisv2/a/en/...l-info/body/lighting/reversing-lights/hw11Pwd

Basically what is SUPPOSED to happen is that the Reversing Light Switch, mounted on the side of your manual transmission, is SUPPOSED to complete a ground to pin #19 of Connector X14261 at the FRM when Reverse is selected, causing the FRM to provide 12V+ to pin #47 of the same connector, and pin #9 of Connector X14260. Note that there are separate connectors and separate wires involved for the Left Reversing Light (Black/Violet) and the Right Reversing Light (Black/Blue).

Old-School DIY Rule: ALWAYS try to identify a SINGLE fault that can cause TWO separate but related failures. :)

In this case, lack of ground at pin #19 of FRM Connector X14261 can cause lack of voltage to BOTH separate wires, sockets & bulbs in the circuit.

I would see if you can backprobe that FRM Connector X14261, pin #19 (Gray/Violet wire) and if so, test by applying a ground via backprobe (Connector attached to FRM) and see if lights come on, or at least you have 12V+ at the two lamp sockets. That's a LOT easier than getting under car to get at the switch. If that powers the reverse lights, then order a new switch and take care of the problem in ONE trip under the vehicle & ONE removal of undertray. Here is TIS procedure for replacing Reversing Switch:
https://www.newtis.info/tisv2/a/en/...electrical-system/61-31-switch-sensor/PwOPaJo

BTW, the TIS circuit diagram is interactive: You can click on any BLUE Component/ Connector ID# and get MORE info such as component location, Connector View, etc.

Please let us know what you find, and we'll move to Cruise,
George
 

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Discussion Starter #4
...[1]I am a bit confused about what you're saying about backprobing the connector on the FRM.
[2]I just retested my reverse light switch once again. I'm getting 7 volts when testing just the wiring. The switch is working perfectly fine.
[3]I do see how this may be a result of a bad ground. How would I go about finding this though...
Since it took over 4 months for you to respond to a Reply I made two hours after your original post, I suppose it is insanity to repeat and expect a different result, but here goes:


[1] "Back Probing" a connector involves insertion of a thin probe into the wiring side of a connector socket, to make contact with the metal part of the socket that the individual wire is connected to. There are numerous explanations & YouTube videos if you Google "Back Probe." You can do this (as long as the individual wires of a connector are exposed) without separating the connector from the module or pins to which it is attached.

You do NOT want to apply voltage or ground to any socket of a connector attached to an electronic module unless you ABSOLUTELY know what you are doing & have a reliable wiring diagram and pin out info, BOTH of which are available in/via the TIS link I originally provided. Mis-application of voltage or ground to the wrong pin can quickly ruin the module. TIS also provides "Connector View" of connectors, with pin numbers shown, as well as shape/ configuration. Wire colors also aid correct identification of sockets in a connector.

DO NOT do ANY back probing of a connector which is attached to a module UNLESS you have taken the time to read & follow the wiring diagrams, connector view & wiring colors to properly identify the correct pin, and understand the possibility of module damage IF the probe slips or inadvertently makes contact with the wrong socket/pin.

[2] Specifically HOW did you test the Reverse Light Switch? For me or anyone else to be able to offer any real help here, we need to know exactly HOW you have "tested" things, and WHERE you have measured voltage. You then say: "I'm getting 7 volts when testing just the wiring. The switch is working perfectly fine." There should NOT be ANY voltage at the switch. If you are measuring and reporting voltage at ANY point, please be specific exactly what pin of what socket, and/or what wire color. As explained four months ago (post 2 of this thread) the switch merely completes a GROUND signal or applies ground to Pin #19 of Connector X14261 attached to the FRM (Footwell Module) which has the ID# A4011 in the TIS circuit diagram I linked previously:
https://www.newtis.info/tisv2/a/en/...l-info/body/lighting/reversing-lights/hw11Pwd

Please take the time to re-read my post #2 and follow the circuit diagram which that post tries to explain. MOST fundamental in that explanation: There are TWO separate voltage outputs from the FRM to the completely separate "backup lights" on either rear lamp cluster: (1) Voltage to the Left backup light is supplied by Pin #47 of Connector X14261 via a Black/Violet wire that runs to the Left backup light (NOT connected in any way to Right backup light).
(2) Voltage to the Right backup light is supplied by Pin # 9 of Connector X14260 (different connector at FRM) via a Black/Blue wire that runs to the Right backup light. Note once again that the Black/Blue wire and the Black Violet wire are completely independent of each other. While it is POSSIBLE that your vehicle has a fault in each separate wire, it is UNLIKELY. Statistically, a single system fault that results in NEITHER lamp lighting is MORE LIKELY.

[3] As the TIS circuit diagram shows, a Ground connection is supplied to the Transmission Reversing Switch (S8511) via a Brown wire from Connector X6462, located in the E-box. Here is the TIS "Installation Location" for X6462:
https://www.newtis.info/tisv2/a/en/e90-325i-lim/SHZhAGE

The switch, when reverse is selected, closes the contact to supply that ground connection to Pin #19 of Connector X14261 at the FRM, via the Gray/Violet wire. So what I would suggest as the QUICKEST/ SAFEST way to test the switch (without having to get under the vehicle) is to DISCONNECT X14261 from the FRM, and see if you have continuity to ground at socket #19 (Gray/Violet wire) when Reverse gear is selected.

Measure Ohms in reference to a good, clean ground point and let us know what that reading is. In other words, one probe of the mutimeter on the #19 socket and the other on a good, clean ground (bolthead, etc.) If you are NOT used to testing for continuity to ground or resistance (ohms) this way, test your meter calibration by simply putting the two meter probes together (touching each other), and you should see an ohms reading approaching zero (.01 ohm or less).

BTW, if you have the Microfilter housing off and E-box accessible, you can just do testing at the E-box, as Connectors X6462 (the origin of the ground signal to the switch) and X6011 (the connector between the ground signal from the switch to the FRM) are BOTH in the E-box. Here is the "Installation Location" for X6011:
https://www.newtis.info/tisv2/a/en/e90-325i-lim/SL92ADs

If you have NO continuity to ground with Reverse Gear selected, then you can (carefully ***x1f609; test the FRM & associated Reverse Lights wiring by simply applying a ground to pin #19 by a safe method (backprobing at X6011 or X14261). With ground applied, light should light with ignition on if everything but ground via switch is working OK.

BTW, probing a connector by inserting the multimeter probe INTO a socket can spread the socket and result in improper contact with the pin when re-connected. Check to make sure the socket #19 has NOT been spread. If it has, then you can simply pry them back together with a "pick" type tool. Something simple like that could be the cause of what seems like a major "electronic failure."


I don't know what your experience level may be with electrical circuits & testing, but if some of this is new to you, just take the time to learn the basics (like reading the instruction manual for a multimeter) and practice doing readings of Ohms, & Volts (no Amps involved here) to get a feel for how to do readings, and what a proper reading should look like. Also, take the time to at least get the basic concept of how the Reversing Light system works with the FRM MODULE effectively acting like a relay where the Switch supplies the ground to the relay coil to close the relay and apply voltage to the two light bulbs, via separate connectors & wiring.

George
Thank you for the help.
I retested my switch and when doing so, I saw on the wire going to the switch, a crimp almost on it giving what would be a bad ground. I straightened it all back up and fixed the exposed wire. My reverse lights are 100% working now. I appreciate the help in understanding the wiring.

If we can, do you mind helping with the cruise control.
I believe my clutch and brake switch are both still good as it won***8217;t start unless I have the clutch engaged, and the brakes aren***8217;t constantly on.

Thank you.
 

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... I saw on the wire going to the switch, a crimp almost on it giving what would be a bad ground. I straightened it all back up and fixed the exposed wire. My reverse lights are 100% working now...

If we can, do you mind helping with the cruise control.
I believe my clutch and brake switch are both still good as it won't start unless I have the clutch engaged, and the brakes aren't constantly on.
Good job tracing/inspecting/repairing the wiring. Most people these days that never had to deal with older vehicles, or vehicles that had been worked on by people who didn't know what they were doing and damaged half of what they touched, ASSume the wiring is NEVER a problem. :rofl:

I have never had to research the cruise control on my vehicle or any other E9x. My understanding is that on the simpler models, the DME does all the cruise control processing unless you have an option such as ACC (Active Cruise Control). Do you know what if any Cruise Option you have, and have you found a circuit diagram for any part of the cruise system. I'd like to learn what circuit diagrams exist in TIS, Bentley, etc. for my own basic system (NO ACC Option). If you don't know what options you have, you can enter your VIN in one of the Decoders, such as this:
https://www.etkbmw.com/bmw/EN/vin/decoder/online

Here is a description of the three different cruise options:
https://www.newtis.info/tisv2/a/en/.../cruise-control-with-braking-function/XZvTnm0

Please let us know about your Cruise Control,
George
 

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Good job tracing/inspecting/repairing the wiring. Most people these days that never had to deal with older vehicles, or vehicles that had been worked on by people who didn't know what they were doing and damaged half of what they touched, ASSume the wiring is NEVER a problem.
I assume problems with electronics are bad connections until proven otherwise, and it's saved quite a bit of time and money. A close second would be bad caps, but not so much with cars.
 

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Discussion Starter #7 (Edited)
Good job tracing/inspecting/repairing the wiring. Most people these days that never had to deal with older vehicles, or vehicles that had been worked on by people who didn't know what they were doing and damaged half of what they touched, ASSume the wiring is NEVER a problem.


I have never had to research the cruise control on my vehicle or any other E9x. My understanding is that on the simpler models, the DME does all the cruise control processing unless you have an option such as ACC (Active Cruise Control). Do you know what if any Cruise Option you have, and have you found a circuit diagram for any part of the cruise system. I'd like to learn what circuit diagrams exist in TIS, Bentley, etc. for my own basic system (NO ACC Option). If you don't know what options you have, you can enter your VIN in one of the Decoders, such as this:
https://www.etkbmw.com/bmw/EN/vin/decoder/online

Here is a description of the three different cruise options:
https://www.newtis.info/tisv2/a/en/.../cruise-control-with-braking-function/XZvTnm0

Please let us know about your Cruise Control,
George
Looks like my reply didn't go through from my phone. I have the 540 with braking.
I was reading some others posts with the same conditions and receiving the same consistent errors from inpa I think it may be the YAW sensor.

https://www.e90post.com/forums/showthread.php?t=1349494
 

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