2000 Electrical Problems, ASD / Elec Fan Pulse

Hey there guys...hope you can help.

I got a 2000 Jeep XJ in my driveway that I purcahsed wrecked. Hit easy on the front right. Air Bags are blown...I have fixed of few of these.

I had a bad fuel pump / sending unit...so I replaced that.

When I turn the key to the pre start position, the ASD relay pulses and sometimes my elec fan and AC pump clutch (engage clicking) will pulse with it. I have good gas to the rail. Sometimes the relay is erratic and makes the fluttering noise, like it is bad.

I crank the engine over and it wants to start and usually does not. If I am persistant and give it some gas I can get it running and it runs great...no pulsing.

Turn it off and try again, no dice. It will pulse and the relay makes a hell of alot of noise. I have swapped out 5 diff relays. I check the codes and it is not tossing any codes, but the airbag light is on. I dont think that would affect anything?

I ran new grounds everywhere, new battery and still does the same thing. When I try to start it, and it tries and fails....I figured out I have to take the key back to the off position and then run clear back to start.

I am stumped big time? Any help will be appreciated.

Steve

Checked a ton of plugs this morn and they alll look good and tight.

Tried to start in neutral and jiggled the shifter, does not seem to be a NSS issue.

Tested for continutiy (ground) from the black battery lead to the firewall and by the ECU...all was good there.

I got it started again, but had to give it gas while cranking it...

I am almost positive it has something to do with the ASD relay and the PCM....but cant figure out what. Everything is too erratic.

Steve

maybe the iac not working???

also can you post pictures of the areas hit. make it easy to figure out.

Here is a picture of the hit, very light. But the air bags were blown.

I also changed the plugs and checked the coils.

I want to take the ASD relay see if a 50lb hammer fixes it.

Can it be the PCM is messing up the ASD relay and things are just not working, but are working on a pulse?

Steve

It could easily be a bad battery. With the engine off and the lights on test the battery voltage.

check all the wires and connectors. it looks to me that things got alittle shifted.

I think I got it figured out. I got a test light and started poking around in the relay box. The ASD relay has to be the problem...so I dug into my memory and remmber which should be powered and which should be ground.

The PCM sends a ground to the ASD relay to close the connection and allow all the circuits to run properly.

So I took my light and tested the pins...found out the ASD relay does not get power all the time, only when the key is turned on...so this is a FYI.

I jumpered the ground, by shoving a wire in the hole and then the relay on top and then grounded the wire to the battery. Turned the key to on and all worked great...the Leak detector pumped and stopped, no fans going crazy.

The car started right up and ran...

So the PCM is not sending the ground needed to make the ASD work properly. From what i read and know, must be a bad PCM.

I hope this helps a ton of people...

Sort of a trick...since the ASD relay does not get power all the time...a quick fix and or work around would be to run a ground from the relay to the battery and the ASD will see that the system is GO all the time...this will get you out of a jam. If you look at the relay holder from the pass side fender, the far left slot is the ground. I can post a diagram if needed?

Thanks for everyone trying to help me.
Steve

So the PCM is not sending the ground needed to make the ASD work properly. From what i read and know, must be a bad PCM.

Click to expand...

doubtfull the ECM has to have a good ground to send in the first place

check the wire from the pcm to the asd relay. it may have been nicked in the attack.

I will check that wire tomorrow...I need to figure out in the book which one it is.

When you say doubtful...and ECM...I hear ECM, ECU, PCM...what is the correct name?

And why doubtfull, I tested for ground all over...and even grounded the PCM at the unit. A old time Jeep guy told me that if your not getting a ground to the ASD, it is either a bad / nicked wire or bad PCM. Please explain langer1...I want to be sure so I dont go getting a PCM and it be worthless.

Thanks again for everyones time,
Steve

ASD relay pulses and sometimes my elec fan and AC pump clutch (engage clicking) will pulse with it.

Click to expand...

All this points to a bad electrical connection. Solid state outputs like used in the PCM either work or don't. 90% of the time when they fail they also fail on.
The other thing is a failed output should throw a code like ASD circuit malfunction.

thanks a ton...I am going to search the wire today. I have a buddy at a salvage yard that let me pull an 2000 computer with same crysler part number.

I will let you all know what the problem was.

steve

The ASD also has an INPUT to the ECM be sure and check that also.
With the key on its suposed to come on for only 3 seconds along with the Fuel pump relay. A short in the o2 sensor would cause a voltage drop and an the ASD to turn off early.

Update:

I tried the new ECM and it did not fix the problem...so I can eliminate that.

I found the ASD ground wire and did a continuity test and it came out good.

I found the 2 grounds that go to plug 1/black (pin 31 and 32) and grounded them to the battery....nothing changed.

The only way I can get the engine to work great is ground the relay out myself and it starts and runs like a champ.

Would the blown airbags be cutting the ASD out?

The O2 sensor wires looked good, all wires look good from what I can see.

Looking for more help,

Thanks
Steve

Could be the crash switch, look under the driverside kick panel for a black box with a reset button.

Just went out with a flash light and took the drivers side kick panel off and there is no crash switch there. I did not think it had one.

What other factors can effect the workings of the ASD relay?

I guess what I mean...what triggers the ECM to not allow it to work...lets just say all ground are good and there are no broken wires.

Thanks
Steve

I printed some detailed wiring diagrams...tonight is wire night.

but any other insight is much appreciated.

Steve

Well tonight was holy crap wire fest.

I check almost every plug, wire harness...cleaned. Grounded stuff, and check a ton for PCM continutiy.

I get a ground from the PCM to the ASD relay but it is week...so the only way I can have a nice functioning vehicle for now is with a inline splice to the DRK BLU/YLW wire to the chassis.

Tha is only temporarily...I will get to the bottom of this.

I did notice something that I never even looked for before....after a min of the relays and crap going nuts...I get a "NO BU5" on my dash....

Steve