On my 1996 XJS 4.0L the air pump does not shut off - even after the car is turned off (and warmed up). I pulled the fuse which obviously shuts the air pump off, but if I plug the fuse back in while the car is warm the pump begins to run. If I wait overnight and let it cool down I can reinsert the fuse and the pump does not operate until next start up.
I was thinking the relay might be bad so I checked the owners manual which indicates the air pump relay is on a bank of 6 relays under the hood (left side by fuse box) and the base is green in color (all the other 5 relays are indicated as blue). Issue is there are only 5 relays on the bank - not 6 as indicated - and all are blue. Before I go pulling each relay one at a time, I thought I'd ask if anyone knows where the air pump relay is located (if there even is one) or if there may be another issue I should be looking into.

 

The Jaguar Electrical Guide has a section called FRONT MATTERS.
The location of all relays is on a page all by itself.
Could be the 'crappy' blue HELLA relays???

bob

 

Unless you have an emesion testing requirement leave it idle. It's function is limited at best, even when working well.


As an aside, do you have a driver's manual, it might help finding it.
My Jeep does. Not sure about my Jaguar!!!


Carl

 

This was quite helpful. i wound pulling each relay and it happened to be the one nearest the firewall which was the first I pulled - it's a blue hella. Stopped by the local dealer this AM to get the closed relay but not surprisingly it's not in stock and it will take a couple of days. Not surprisingly (again) there is an updated relay for replacement.