Club 80-90 Forums

I have a westfalia van, and as far as I know it is mostly standard. Electrically, there are a couple of extras, which I shall investigate (extra small fuse box, and a couple of switches that don't do anything)

When I was doing some work on the heater electrics, I took off the positive cable from the main battery. This cable was still live and showed 12v when I tested it.

Is this right? I assumed (with no knowledge) that it should be isolated from the positive side of the leisure battery.

There must be people here who know the answer to this.

Am I being shunned for stupidity?

Possibly the heater runs from the leisure battery.
Which engine you have? Diesels have engine battery in the back beside the engine and leisure under one of the front seats.

ZsZ wrote:Possibly the heater runs from the leisure battery.
Which engine you have? Diesels have engine battery in the back beside the engine and leisure under one of the front seats.

Thanks for the info.

It is petrol. DG.

I can't find much info on the westfalia electrical setup.
Are the batteries supposed to be separated? Or am I barking up the wrong tree?

zoona wrote:

ZsZ wrote:Possibly the heater runs from the leisure battery.
Which engine you have? Diesels have engine battery in the back beside the engine and leisure under one of the front seats.

Thanks for the info.

It is petrol. DG.

I can't find much info on the westfalia electrical setup.
Are the batteries supposed to be separated? Or am I barking up the wrong tree?

On petrol vans both batteries are under the front seats.
Main battery under the passenger, leisure under the driver seat (LHD westfalia).
they are combined by a small 40A relay under the driver seat when the charge light is off and the alternator is charging

Tested the relay, and I think it is "feck".

There is a connection from 30 to 87, when I think that should only be connected when there is a voltage across 85 and 86.
Have I got that right?

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The relay makes contact between 30 and 87 when electicity flows through 86 and 85.
The blue wire connected to 86 is the charge indicator circuit (alternator exciter) which is +12V when the alternator is charging and grounds through the red wire with black tracer at 85 which is connected to the starter circuit.
Its a safety fearure to avoid connecting the two batteries when the starter is engaged.
So if the alternator is charging the relay is engaged and the switch between 30 and 87 is connected.
Howewer there are westfalias with 5pin relay which has two 87 contacts. That is wired in a way that the fridge has +12V only with the engine is running.

ZsZ wrote:The relay makes contact between 30 and 87 when electicity flows through 86 and 85.
The blue wire connected to 86 is the charge indicator circuit (alternator exciter) which is +12V when the alternator is charging and grounds through the red wire with black tracer at 85 which is connected to the starter circuit.
Its a safety fearure to avoid connecting the two batteries when the starter is engaged.
So if the alternator is charging the relay is engaged and the switch between 30 and 87 is connected.
Howewer there are westfalias with 5pin relay which has two 87 contacts. That is wired in a way that the fridge has +12V only with the engine is running.

Ok, that's what I gathered. Relay is dead then.

Should I disconnect the leisure battery until I replace the relay? As it will be connected when starting the engine at the moment.

If you pull the wires from the relay then they wont be connected. Just be sure none of the wires can touch the chassis.
Probably the connectors inside the relay are welded together by some big current caused by a flat leisure battery.
You can carefully pry the relay apart and check/clean the switch inside. Although ist a standard 40A relay which can be bought cheap.

ZsZ wrote:If you pull the wires from the relay then they wont be connected. Just be sure none of the wires can touch the chassis.
Probably the connectors inside the relay are welded together by some big current caused by a flat leisure battery.
You can carefully pry the relay apart and check/clean the switch inside. Although ist a standard 40A relay which can be bought cheap.

Thanks.

I've got one in order now.
It's mostly staying in storage at the moment, but if/when we next use it I'll disconnect when using stuff.

Thanks very much for the help.