What is the specific relay part # for the A/C clutch in a 1988 Vanden Plas, and where can I purchase it? Thank you.

 

I believe most of the relays on the firewall are interchangeable (at least on a 94) and the A/C clutch relay is nothing special. Just get one with the same rating and pinout as the one you're replacing. Jaguar recommends sealed ones rather than the blue Hella ones. Your local parts store should be able to set you up with the relay you need.

I replaced all mine years ago with aftermarket units, no issues since.

You can swap out the relay to see if it's the problem - usually the reason the relay won't energize is due to the low pressure switch detecting a low refrigerant condition. If that is the case, the relay won't start the compressor to avoid damaging it.

Larry

 

I can engage the compressor by jumping pins 30 and 87, so I think it is good but the relay may be bad.
I was confused because all the relays surrounding the A/C clutch relay are yellow, and the A/C clutch relay is black. The yellow relays are Hella 4RA 12V 003 510-32, but the black A/C clutch relay is Hella 4RA 12V 003 510-33. Is the last number on the relay (32 vs 33) only the color, or something else? A search for these relays only result in used ones. Would any 12V relay of the same pin configuration work?

 

I believe the relays are interchangeable so yes the relay with the same config should work.
Jumping the contacts to energize the compressor momentarily is a good way to see if the compressor runs, but as that technique by-passes the low pressure switch it is no guarantee that the relay is bad.
As I mentioned earlier, low refrigerant is the primary reason the system won't run/energize the relay. From your symptoms, It's possible you are just low on gas and need a recharge.

Larry

 

Thank you. I am going to have the system evacuated and then charged and checked for leaks by a professional. I will report back their findings.

 

Hi Ernest,

Sorry to join your thread late. Larry is probably correct regarding your refrigerant charge.

If you learn that you do need an A/C relay, one thing to be aware of is that the original Jaguar relays have a resistor and diode in parallel with the relay coil:





The purpose of the resistor and diode is to protect the climate control computer from voltage spikes caused by the collapse of the magnetic field when the relay is de-energized.

I have not found relays with both a diode and resistor, but I have found that the Bosch 0 332 019 103 does have a resistor across the coil and is a 30 amp relay suitable for most circuits in Jaguars.



If you search the part number you'll find sources for these.

Cheers,

Don

 

Don B to the rescue.....always on point. Thanks.

 

Is that the A/C compressor relay Don?

Larry

 

Hi Larry,

That's the A/C control module relay - I just grabbed the snip quickly while on a break. The A/C compressor clutch relay is the same type:




Most or all of the original relays in the XJ40 have the resistor & diode in parallel with the coil, whether they are the 4-pin or 5-pin types. The ABS overvoltage relay has an additional Zener diode across the terminals

Cheers,

Don

 

The shop evacuated my A/C system, put dye in, and recharged it. They said it was low on refrigerant and there might be a leak and, if there is, the dye will reveal the leak over time. For now it is blowing nice and cold.
Larry and Don B thanks your help.