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Mar 13, 2014 | 12:15 PM

#16

CCKen

CF Veteran

Joined: Aug 2010

Posts: 8,357

Likes: 103

From: Canton, MI

Year: 1999

Model: Cherokee

Engine: 4.0

Quote:

Originally Posted by Roler

Very. Closure is good. Thanks.

For future reference: switching a suspected bad relay with a known good one, can be helpfull to verify it being the relay thats bad.
Reminds me of that time my e-fan relay going pear shaped(would intermittently stay closed): e-fan would continue running after engine shut down. Switching it with the ASD would leave me with the XJ continue to run for 2 seconds after the key was already out....funky.

Generally, swapping relays to isolate a suspected relay fault is limited to using the fan relay as the test specimen - on other than 00/01 XJ's due to different style relays - is the way to go. I wouldn't recommend swapping the fan and the ASD relay on the 00/01 XJ's due to the possibility of screwing up the PCM. The PCM is sensitive to the ASD relay input signal.

Mar 13, 2014 | 12:43 PM

#17

Roler

CF Veteran

Joined: Jan 2012

Posts: 3,170

Likes: 312

From: Australia

Year: 1997 (RHD)

Model: Cherokee (XJ)

Engine: 4.0 ltr

Quote:

Originally Posted by CCKen

Can't speak for the 00/01. Interesting: is the relation between ASD and PCM in 00/01 specifically different that older years? Or am I reading this wrong?

Mar 13, 2014 | 12:58 PM

#18

CCKen

CF Veteran

Joined: Aug 2010

Posts: 8,357

Likes: 103

From: Canton, MI

Year: 1999

Model: Cherokee

Engine: 4.0

Quote:

Originally Posted by Roler

Can't speak for the 00/01. Interesting: is the relation between ASD and PCM in 00/01 specifically different that older years? Or am I reading this wrong?

It's the same for earlier years as well.

Edit: I did read in my FSM that it is cautioned not to jumper the ASD relay (pin 30 to 87) because PCM damage may occur.

Last edited by CCKen; Mar 13, 2014 at 01:01 PM.