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Electrical issues - where to start...

Discuss problems you have had or are having with your Z4
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Jalfrezi
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Location: Bristol

Electrical issues - where to start...

Post by Jalfrezi » Thu Feb 07, 2019 11:46 am

When I bought my car (2003 3.0), it had a parasitic battery drain, as I drove it lots it never became an issue so I lived with it.

About a year later the central locking stopped working, and again I just lived with that.

Then water got into the boot, and my amp blew...

Now I feel motivated to fix these things, and I'm not sure where to start. I'm thinking that the central locking could be the GM5 module, and possibly this could also cause the battery drain. So tempted to get the relays replaced 1st before I do any further work. Does that sound a likely cause, and sensible 1st step?
2003 E85 3.0i, 144000 miles and counting...

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ph001
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Location: N. Yorkshire.

Electrical issues - where to start...

Post by ph001 » Thu Feb 07, 2019 12:46 pm

I can replace the relays for you at very reasonable cost which will probably sort your central locking but not your power drain issue - that could be the amp so I would completely disconnect that to eliminate it. If you still have power drain issues you need to start looking at volt drop across fuses to try to isolate the problem. A battery going flat in 3-5 days tends to be some dodgy ancillary item like a gaptech module or an internal light staying on (the centre rear cubby behind the seats is a favourite). Where are you located?
2007 E85 Z4 3.0Si manual :driving:
19" CSL's | Eibach Springs | Aeroskirts | Z4M front bumper | Clear brake light | ZHP | RCH+| Stubby

2004 E46 M3 coupe manual - gone but not forgotten.

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Jalfrezi
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Posts: 88
Joined: Sat Aug 06, 2016 3:25 pm
Location: Bristol

Electrical issues - where to start...

Post by Jalfrezi » Thu Feb 07, 2019 12:47 pm

Thanks. I'm in Bristol.
2003 E85 3.0i, 144000 miles and counting...

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ph001
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Joined: Mon Oct 31, 2016 5:53 pm
Location: N. Yorkshire.

Electrical issues - where to start...

Post by ph001 » Thu Feb 07, 2019 2:39 pm

Too far for an assist unfortunately, but I can sort your GM5 module if you can remove and post. There are guides on here how to get it out.

I can also have a look at your amp as well if you like but whether or not that is recoverable depends how much corrosion it has on the pcb.
2007 E85 Z4 3.0Si manual :driving:
19" CSL's | Eibach Springs | Aeroskirts | Z4M front bumper | Clear brake light | ZHP | RCH+| Stubby

2004 E46 M3 coupe manual - gone but not forgotten.

Image

Jalfrezi
Member
Member
Posts: 88
Joined: Sat Aug 06, 2016 3:25 pm
Location: Bristol

Electrical issues - where to start...

Post by Jalfrezi » Thu Feb 07, 2019 2:57 pm

Great, thanks
2003 E85 3.0i, 144000 miles and counting...

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