Battery flat - Closed out from Rover 75T - Page 4

macafee2 · 28th April 2019, 12:31

Quote:

Originally Posted by MarkS

As I understand the standard, pin 4 (green) of the 12S socket should be wired directly to the battery positive (via a 10A fuse).
There should be no split charge relay (et al) in the circuit, in the car.

Haynes manual 4292 Rover 75 shows it as being pin 2!

But (British) standards being (EU) standards, who knows.

Perhaps somebody with a 12S socket can confirm this.

you may well be right but alas that does not answer the question

From memory, if there is no split charge then a caravan fridge can result in the car battery being flattened if the caravan is left connected with the fridge on and engine not running, may need to be "overnight". Also the car could use the caravan battery to try and start if the cars battery does not have sufficient puff to start the car.

I think my saloon has suffered this problem as I don't think it has a split charge relay. My tourer has a split charge.

macafee2

MarkS · 28th April 2019, 13:18

From what I understand, a fridge should be connected to pin 6 (which is probably an ignition switched supply).
And a caravan should either have it's own split charge relay, fed from pin 4, or is charged from pin 2 (where the car has it's own split charge relay controlled output), to prevent back-feeding into the car starter motor.

But pre 1999, post 1999 and pre 2006, and post 2006, BS, EN & ISO standards have probably confused things !
And me (easily done) and you !

cb750chris · 28th April 2019, 19:52

Glad to hear the op has sorted the problem.
Ian, Mark is correct, on the grey plug there should be a permanent live.

Pin 2 is the battery charging connection, and should be connected via a split charge relay
Pin 6 is the fridge power, and should be connected via a split charge relay
Pin 4 should be permanently live (via fuse) to simply run interior lights etc (switched in caravan to choose between caravan battery and car battery - the intent being to run from car if there is no battery fitted in caravan)
Obviously this is what should be implemented, but your wiring may be different.

Chris

28th April 2019, 13:18	#32
MarkS Gets stuck in Rover 75 Diesel Tourer, called Perseverance Join Date: Nov 2011 Location: Bournemouth Posts: 664 Thanks: 189 Thanked 157 Times in 108 Posts	From what I understand, a fridge should be connected to pin 6 (which is probably an ignition switched supply). And a caravan should either have it's own split charge relay, fed from pin 4, or is charged from pin 2 (where the car has it's own split charge relay controlled output), to prevent back-feeding into the car starter motor. But pre 1999, post 1999 and pre 2006, and post 2006, BS, EN & ISO standards have probably confused things ! And me (easily done) and you ! Last edited by MarkS; 28th April 2019 at 13:52..

28th April 2019, 19:52	#33
cb750chris Trader Rover 75 Tourer Join Date: Apr 2011 Location: Portsmouth Posts: 849 Thanks: 201 Thanked 292 Times in 200 Posts	Glad to hear the op has sorted the problem. Ian, Mark is correct, on the grey plug there should be a permanent live. Pin 2 is the battery charging connection, and should be connected via a split charge relay Pin 6 is the fridge power, and should be connected via a split charge relay Pin 4 should be permanently live (via fuse) to simply run interior lights etc (switched in caravan to choose between caravan battery and car battery - the intent being to run from car if there is no battery fitted in caravan) Obviously this is what should be implemented, but your wiring may be different. Chris __________________ Now offering T4 services in the Fareham area Replacement keys programmed / supplied / cut Diesel 135 upgrade available IPK virginisation and T4 matching available Sorry, due to a big change in home circumstances, I am unable to do any large jobs at present, but can still offer evening time diagnostics. Last edited by cb750chris; 28th April 2019 at 20:35..