No Start w/ no BuS on Odometer
 

Hey I have a 2000 XJ with a coil pack that won't start.

With the ignition on, none of the guages work and after 30 seconds I get the no BuS reading. I changed the crank position sensor and it did nothing, and it has spark but no fuel pressure.

Is the next thing to replace the computer? I thought about replacing the fuel pump but I've never heard of a fuel pump throwing a no bus reading.

Pull the horn relay out of the interior fuse block. Then try starting it.

For real? I'm waiting for it to warm up a little out there gonna hit 65 today...

I'll add that to the list. So far I have these things to check before I go ahead and replace the computer:

-Pull the center console out and check the grounds on the computer
-Disconnect and reconnect the computer
-ASD and Fuel Pump relays under the hood
-Pull horn relay

I should add that it has spark, I got it to almost start with starting fluid.

It could be any of the engine management sensors or yes maybe even the computer. Try removing one at a time from the bus and and crank it, see if this resolves the issue.

A lot of ways to attack the issue....https://www.google.com/webhp?sourcei...o%20bus%20code

If it doesn't start/run with starting fluid, probably don't have spark. What is the fuel pressure in psi? What is the exact number of the failure code?

I can't get a reading with my OBDII and it has no fuel pressure, plus I don't hear the fuel pump come on. I'll also try pulling sensors one at a time.

You said you "changed the crank position sensor"

Did you put a new one in?
Where did you buy it?
Did you test the new one before you put it in?

Check the fuses?

It's possible your No Bus error was not caused by the CPS and the engine wouldn't run because it has no fuel pressure.


I would troubleshoot the fuel pressure issue. As mentioned, first check all fuses, then the pump. How many miles are on your XJ?

Your PDC:


Attachment 316206


Relays are marked on the cover of the PDC.


JB Guide someone put together:


Attachment 316207

This is the Air Bag Control Module. Don't mess with it.

I took a CPS off of a running jeep and put it on, so it should be good.
Thanks for the pictures those should come in handy!

Just checked all the mentioned fuses, touched the positive to the negative on the battery to no avail. So the computer is next to where you plug in the OBDII right? I'll disconnect and reconnect that next and check the grounds, then I'll start pulling sensors. Which sensors?

Check the wiring?