P38 battery drain - engineering required

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MSX150

New Member
Posts
111
Location
North Wales
I have what is now quite a rapid battery drain on my P38, I have posted previously and covered the basics, what i would really like is a diagnostics engineer to sort it - can anyone make any recommendations in the North Wales / Cheshire area ?

thanks
 
I have had a new one two years ago, it was one of the first things that was changed, I had the alternator changed before christmas, and they tried to order another one but they were on back order.... since changing the alternator I have gone from 3 days to three hours.... WTF is going on!!!!!!!
 
when you park up, do you park next to you house or some body elses house. are there any new phone masts gone up. you would be shocked how many things can feck then up, if i use my drive my bat is flat in hours. and before anybody saids you need new one.mine is only weeks old and as big as you can get..
 
MSX150 said:
I have had a new one two years ago, it was one of the first things that was changed, I had the alternator changed before christmas, and they tried to order another one but they were on back order.... since changing the alternator I have gone from 3 days to three hours.... WTF is going on!!!!!!!
Click to expand...

Faulty diode pack in the new alternator perhaps. With the engine off, disconnect the alternator and put an ammeter between the cable and the alternator. The reading should be close to zero.
 
I just discovered that the satellite tracker in my Subaru Impreza was drawing 280mA. It's something else I need to sort out now that I have fixed the alternator on my Rangie!

Not on the scale of your current drain but these things add up!

Pete
 
Datatek, I replaced the alternator because the old one was failing the diode check, the battery is quite new and my 4th in three years....

I have now disconnected the blue wire and will charge it up fully and try again...

As stated before, my mechanic had fitted an isolator to the RF, which basically cut to the power to it, this did'nt work, so would disconnecting the blue arial make any difference?
 
MSX150 said:
Datatek, I replaced the alternator because the old one was failing the diode check, the battery is quite new and my 4th in three years....

I have now disconnected the blue wire and will charge it up fully and try again...

As stated before, my mechanic had fitted an isolator to the RF, which basically cut to the power to it, this did'nt work, so would disconnecting the blue arial make any difference?
Click to expand...

Yes; The blue wire is to the aerial embedded in the offside rear quarter glass. Disconnecting it lessens the range of key fob, but, importantly stops the RF unit picking up spurious radio signals such as phone masts, wireless hubs, even doorbells, all of which emit on a similar frequency, thus waking the BeCM, and draining power.
 
Mine has just started to do the same and on investigation a neighbour up the road has just bought a poxy Jeep Cherokee and it is the cause of the problem bloody American crap anyway take the blue wire off and see - I also had a drain due to a faulty lock actuator which would send a signal saying the alarm wasnt armed when it was so check they are all ok
 
MSX150 said:
Datatek, I replaced the alternator because the old one was failing the diode check, the battery is quite new and my 4th in three years....

I have now disconnected the blue wire and will charge it up fully and try again...

As stated before, my mechanic had fitted an isolator to the RF, which basically cut to the power to it, this did'nt work, so would disconnecting the blue arial make any difference?
Click to expand...

I'm not sure if actually disconnecting power from the RF receiver is a good idea, it might just be that the BECM stays awake looking for it. Irishrover would know.
 
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