Front Driver Side Single Relay Function?

[mhead]

Hi All,

I have a 1992 XJ Laredo with 4.0 I6 and AW4 Auto Transmission. It has A/C and heavy duty tow package. It has ABS. This Jeep has the relay/fuse box on the passenger side of the engine bay with the engine control computer located parallel the air box on the driver side.

The cover in the relay/fuse box marks the relays as "AUX. FAN, FUEL PUMP, ABS PUMP, A/C, AUTO SHUTDOWN, STARTER, ABS SYSTEM".

There is another, isolated, relay located on the driver side of the engine bay just forward of the engine control computer and screwed to the front bulkhead.

What function does this relay control?

And, on the topic of relays, what does the AUTO SHUTDOWN relay do?

Thanks!

 

[XJI6191]

I'd always understood that was to switch off the foglights when brights are selected, a legal requirement in many countries - but apparently one that Jeep haven't bothered to comply with. I think the DRL relay's there on Canadian spec. models - but that doesn't really help either.

On a diesel, auto shutdown does exactly that, when you turn off the ignition, instead of having to turn off the fuel & wait for the engine to die but don't think there was a diesel XJ in '92, as it was an export option & - iirc - we didn't get XJ's 'til '94.

 

[mhead]

Thanks for the excellent answer!

Yes, the relay does appear to be wired into the electrical harness as it goes through the front bulkhead to the headlights and other front lighting. Given its isolation it looks like an after thought. I have a FSM which shows a relay in the fog lighting circuitry. All adds up.

Auto Shutdown - diesel makes sense.

Thanks again!