Battery drain, numerous lights on dash car stops

H

Hebrewdiver

Member
Recently I had my gm5 module repaired on 2004 z4 now I’m having problems with the car starting and running. I’m not getting any codes just lights and eventually shutting down. I put in a new battery and all lights went away and car ran good. I drove about 30 miles during the day no problems but when I came back it was dark and I had to turn on headlights. About 20 minutes into drive light started coming on, abs, brake, tire pressure, some gear symbol, radio stopped playing, dash light turned off, car started running bad and eventually stopped. I called a tow truck and the driver hooked it up to a jump box and the car started with none of the trouble lights on. What can be causing this? Could the alternator be bad? Could the gm5 module be causing this? I’m attaching a picture so you can see the lights that are on. What’s the best way to troubleshoot? Start car, take the negative battery cable off and if car stops running it’s a bad alternator, that’s what I was told by an old school mechanic. Any help would be greatly appreciated. This picture does not show al the lights
 

Attachments

  • IMG_2409.jpeg
    IMG_2409.jpeg
    856.9 KB · Views: 1
Don't disconnect the battery while it's running or you'll destroy every electronic module in sight.

Just measure the voltage at the under bonnet terminals. Stopped it'll be 12 and a bit volts, running it should be 14v.
 
As above, first check is the battery voltage.
Closely followed by a full system scan.
First thoughts are that the alternator isn't charging properly.
 
EZ that’s what I was thinking alternator issue but before I take it out and buy another I wanted to get the advice of some knowledgeable people. I’m going to try checking the voltage at the bonnet terminal, where is the bonnet terminals…lol. I have a little inexpensive voltmeter. I hope that works.
 
Hebrewdiver said:
EZ that’s what I was thinking alternator issue but before I take it out and buy another I wanted to get the advice of some knowledgeable people. I’m going to try checking the voltage at the bonnet terminal, where is the bonnet terminals…lol. I have a little inexpensive voltmeter. I hope that works.
Click to expand...
Check across the battery terminals.
You can possibly replace the diode/brush pack on the rear of the alternator in situ depending on engine type. I’ve done it on M54s but not sure of access on others
 
enuff_zed said:
Check across the battery terminals.
You can possibly replace the diode/brush pack on the rear of the alternator in situ depending on engine type. I’ve done it on M54s but not sure of access on others
Click to expand...
I took the alternator out and took it to the parts store and had it tested…it failed. So I guess I will try to try and change out the voltage regulator. I have checked a few parts stores and they don’t have them. I checked a few dealers and the prices are as high as a new or remanufactured alternator. Would you recommend Amazon? as I saw a few on there. How difficult of a job is it? Any suggestions on where else I might find one? I’m in the US.
 
To swap it is very easy especially as you have taken it from the car. In the UK we can get them from eBay
 
You must log in or register to reply here.
Back
Top Bottom