P38 battery drain in 2 days

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If you have multi meter , turn it to Dvc 20 ....put red lead to positive side of battery , black on negative side ........reading should be 12.5 plus / minus a couple of points ( dependant on temp ) . Then turn on engine should increase to around 14.5 , if it does that means altenator is working . Turn a few things on high beam / heater/ etc the reading should drop then come back up .
Turn everything off again ...leave engine running 10 mins / go for quick run around to get some juice into battery ..turn off engine ...turn lights on for one minute then turn off ........reading should drop back down to 12.5 +/- a point or two ( temp) if it goes below that and keeps going ........batteries not good
 
disco 1 harrogate said:
If you have multi meter , turn it to Dvc 20 ....put red lead to positive side of battery , black on negative side ........reading should be 12.5 plus / minus a couple of points ( dependant on temp ) . Then turn on engine should increase to around 14.5 , if it does that means altenator is working . Turn a few things on high beam / heater/ etc the reading should drop then come back up .
Turn everything off again ...leave engine running 10 mins / go for quick run around to get some juice into battery ..turn off engine ...turn lights on for one minute then turn off ........reading should drop back down to 12.5 +/- a point or two ( temp) if it goes below that and keeps going ........batteries not good
Click to expand...
Alternator regulator set point is 14.2 volts on the P38 not 14.5 volts.
 
Thanks for all the advice guys, all taken on board, I feel quite ill so have not felt up to doing any checks. I ordered a ctek mxs 5.0 charger , the car doesn't get much use so will keep it hooked up whilst parked.
 
If it is an RF issue it may burn out your locks. Really worth checking that one. Brian's fix is apparently dead cheap and easy and will save your locks!

If it is the alternator then it will only be a matter of time before it dumps you somewhere - so you need to check that too!
 
No, it is the signal confusing the BECM that cycles the locks continuously and eventually burns them out. If you disconnect the battery that will solve it, or disconnect the power to the RF unit under the rear shelf. By the time you've done that (and it only takes 5 minutes) you might as well fit Brian's second fob fix. Costs less than a tenner, I think.
 
Grrrrrr said:
No, it is the signal confusing the BECM that cycles the locks continuously and eventually burns them out. If you disconnect the battery that will solve it, or disconnect the power to the RF unit under the rear shelf. By the time you've done that (and it only takes 5 minutes) you might as well fit Brian's second fob fix. Costs less than a tenner, I think.
Click to expand...

Disconnecting the battery could cause more problems as I know to my cost. I did the mod for less than £3, you need to shop around on the Bay of Flea for a remote "jog" switch which only makes the circuit when pressed.:)
 
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