Anyone good with electrical? Need Help!

[spadil2]

Anyone good with electrical problems and can help guide me? Dash is going crazy and im pretty sure either a wire is corroded or a module is fried and throwing off other modules but need guidance. Thanks!
2011 128i

[NorthernDancer]

1. How long have you owned the car? Less than a month or two is very different than 2 years or more.
2. Check for thightness of positive and negative battery cables in engine and trunk. If any loose, remove and clean.
3. Google "BMW ground wire corrosion". There is a ground wire very low on drivers side of engine-big issue with BMWs of the last 20 years or more.
4. Find a BMW indy garage in your area.
5. Join BMWCCA to get expert help from other BMW owners in your area. Other owners will tell you of best indy BMW garages.

[spadil2]

Originally Posted by NorthernDancer

1. How long have you owned the car? Less than a month or two is very different than 2 years or more.
2. Check for thightness of positive and negative battery cables in engine and trunk. If any loose, remove and clean.
3. Google "BMW ground wire corrosion". There is a ground wire very low on drivers side of engine-big issue with BMWs of the last 20 years or more.
4. Find a BMW indy garage in your area.
5. Join BMWCCA to get expert help from other BMW owners in your area. Other owners will tell you of best indy BMW garages.

1)I’ve had it for a few years lol, sunroof drain was clogged and never did anything about it until now my dash is freaking out lol.
2) Ive tightened those cables and checked all cables in battery area and they all look good.
3) Will check the ground wires underneath the car, car is missing a few under trays so..
4) I’ve done everything myself so far (except vanos recall) so trying as much as I can to fix this before I call it quits and send it to a shop who charges me 1k+ to find an electrical issue on a car that has 190k miles and isn’t worth much..

[NorthernDancer]

$1K?. Then find yourself a different shop, BMW indy! They can locate the specific ground wire immediately and replace it immediately often with their home made wire and should be less than $200.00

[spadil2]

Originally Posted by NorthernDancer

$1K?. Then find yourself a different shop, BMW indy! They can locate the specific ground wire immediately and replace it immediately often with their home made wire and should be less than $200.00

Pretty sure it’s a corroded wire somewhere or a module that’s faulty and taking down the rest of the can system, figured it would be pretty expensive

[zx10guy]

I had my dash go crazy once. It was a while ago while the car was still pretty new. Dash would light up like a Christmas tree and then go dead but the car kept running. Brought it to the dealership since the car was still under warranty. They found water in one of the cavities in the trunk which shorted out the junction module/box. They looked for the source of any water leak but couldn't find anything. The only plausible reason was that I had my car at said dealer's body shop for a minor bump/issue to the rear bumper. So something could have happened with the car there with water intrusion. In the end, I didn't get billed for any work done which also included the CAS module which was also found to have shorted out due to the keyless entry and ignition not working.

You might want to look back there to see if there is any water. There have been reports of water getting into the trunk from the outside due to failed seals and such....typically from the rear tail lights.

[spadil2]

Originally Posted by zx10guy

I had my dash go crazy once. It was a while ago while the car was still pretty new. Dash would light up like a Christmas tree and then go dead but the car kept running. Brought it to the dealership since the car was still under warranty. They found water in one of the cavities in the trunk which shorted out the junction module/box. They looked for the source of any water leak but couldn't find anything. The only plausible reason was that I had my car at said dealer's body shop for a minor bump/issue to the rear bumper. So something could have happened with the car there with water intrusion. In the end, I didn't get billed for any work done which also included the CAS module which was also found to have shorted out due to the keyless entry and ignition not working.

You might want to look back there to see if there is any water. There have been reports of water getting into the trunk from the outside due to failed seals and such....typically from the rear tail lights.

Yeah a lot of people have told me the rdc module in the trunk gets water but in the compartment I don’t have any modules nor was there water. Chat GPT does point towards JBE box being bad though.. am trying to run ista while car is fine and when dash goes crazy seeing which module goes off first. Don’t want to spend hundreds on parts that im not sure would 100% fix it and the JBE needs to be coded too so..

[GoRomeo]

How about power regulator or alternator? Have you tested those? I think I ve seen post related to this issue.

[spadil2]

Originally Posted by GoRomeo

How about power regulator or alternator? Have you tested those? I think I ve seen post related to this issue.

Alternator reads fine though.. changing regulator today and if not i could change alternator and if not then return it then probably battery last since I have to code that but im reading good volts on battery and alternator

[ShocknAwe]

Post the codes please.

There's a sequence for working through some CAN and BSD issues. Several good threads on E90post which thanks to our cars being virtually identical under the skin is highly applicable.

First step is deciding if you're on individual problems or a power supply issue.

Test the battery voltage.

[spadil2]

Originally Posted by ShocknAwe

Post the codes please.

There's a sequence for working through some CAN and BSD issues. Several good threads on E90post which thanks to our cars being virtually identical under the skin is highly applicable.

First step is deciding if you're on individual problems or a power supply issue.

Test the battery voltage.

Think these were after i cleared it, passenger seat module is disconnected as i was trying to see if that’s the problem. The voltage is fine, even replaced alternator and voltage regulator and still same problem. Im starting to think it’s the JBE, when the dash is going crazy the steering wheel buttons don’t work, interior lock button and dome lights.. then after awhile the needles will freeze and AC drops out. Thinking water damage in the JBE? ive inspected the wires under carpet and they seem fine.