Westfalia refrigerator relay low voltage issue

[localmusicfan]

The refrigerator relay in my 82 Westy has not been triggering, while the van is running, to get power to the fridge. There are two terminals labeled 86 which both have 12v. These work correctly for the sink. Voltage to terminal 85, the blue wire, is only 1.5v when the ignition is engaged. This doesn't appear to be enough voltage to trigger the relay. If I apply 12v to terminal 85 the relay clicks.

Here is the schematic on the back of the relay:

This is the part # info:

So is my relay bad for not tripping at 1.5v or is that incoming voltage not correct for the relay?

[localmusicfan]

It looks like the Bentley manual shows the blue trigger wire is feeding off the OXS indicator light circuit. Is that why I am only seeing 1.5v via the trigger at the relay? Is it due to voltage from the OXS or from the resistor that appears in the Bentley wiring diagram just before the OXS indicator light?

[Dampcamper]

Looking at the '82 Camper wiring, one side of the relay coil is the Blue wire coming from the alternator. When the engine is spinning and the alternator is putting out voltage, you get + voltage. If you just have the ignition switch on you will not have + voltage.
The other side of the relay coil is connected to the starter solenoid wire (Red/Black) so when your ignition switch is in "Start" it has + 12 volts on it and when you are not in "Start" the low electrical resistance of the solenoid provides a good-enough ground that the refer relay can use it for the "low" side. This connection shuts off the relay when the starter is engaged, saving all those amps in your battery for the starter.
In your second photo it looks as if the coil just goes to ground via a brown wire? This would work almost the same as described above but would lack the shut-the-fridge-off-when-you're-cranking feature.
Also I see some divots in the insulation that indicate something was spliced in to those wires using ScotchLock connectors? No telling what could have happened there.
But the relay is not supposed to power on the fridge if the engine is not spinning, it won't come on just because the key is "On".

[crazyvwvanman]

The blue wire only has a higher voltage when the engine is running and the alternator is charging. So that 1.5 volts with key on but engine stopped is fine. (the 1.5v comes from the instrument cluster alt warning circuit bypass resistor) Start the engine and rev the motor a second, then check the voltage on the blue wire. Should be above 10v then.

As for the brown ground wire for the relay coil, that is how some Westys came. Most others have a red/black wire that uses the starter solenoid coil as a pseudo ground. The red/black ground method isn't needed and can cause trouble. I usually unplug it from vans that have it and use a ground jumper like that brown one your van has.

Mark

[localmusicfan]

thanks crazyvwvanman.....that was it! Blue Alt wire from the instrument panel only delivers 1.5v on initial start up until engine is reved then I get 15v and the relay engages. Problem fixed.

[Dampcamper]

[amplemanmc]

Hi, this is the closest thing I found to fuse location S23 and S61 for fridge on DC and AC. Would you guys happen to know where I can find those fuses by any chance?? It would be VERY helpful!

[crazyvwvanman]

They are usually behind the driver seat, in the corner. Look for a small dark brown or black cover with a screw in the middle.


80/81 and some 82 don't have it and there is a different camper wiring diagram for those.
A lot of versions of the Bentley show the wrong camper diagram for these early years.

Mark

[amplemanmc]

Thanks for your help Mark, but unfortunately, I could not find those fuses S23 and S61 on my 82 Diesel van. There's nothing behind the driver's seat that looks like what you described me

[drip]

My82 diesel has the two fuses in the compartment behind drivers seat. Factory wiring.