P1698 mixed with some other stuff

Ok, here is where I'm at:

Jeep is setting the P1698 code (No CCD message from TCM) and the airbag light comes on then I have no gauges. I have done the TSB for the gauge cluster and nothing has changed, swapped the CPS, cleaned and dielectric greased the TCM connections and ECU.

While searching the internet seen someone mention the harness by the drivers side kick panel so on a whim I pushed the door unlock button and my airbaglight turned off and all my gauges came back for a few minutes then came back on and no gauges again. So after some fiddleing I decided to delete the P1698 code and hold the unlock button down while I scanned for codes, no codes present! I scanned for codes a few different ways all while holding the door unlock button in, still no codes. As soon as I let go of the unlock button and scan for codes it sets the P1698 code, turns airbag light on, no gauges again.

Right now I have the door off to visually check the harness since I know this can be a common problem area. Only thing I see is its pretty wet so far. To be curious I thought I would call the dealer to see how much a new harness is and they want $450 bucks!

I think I have isolated the problem to the harness or the switch. What I need to know now is how I should diagnose these two things with my multi-meter, what kind of resistance should I be seeing thru the harness wires?

Everything works and runs fine and no codes set as long as I hold the darn unlock button in.

I'm working on 99' XJ, AW4, 4.0, power door/windows.

TIA

I would pull back the rubber flex boot by the door hinges and see if you have any broken wiring there. Those harness tend to flex when the doors are open and the wiring will break. I doubt its the switch sounds more like a wiring issue. I have never heard of a door lock switch bringing down the bus.

OK, I told you on the CO thread I would look into this a little. It seems the driver's switch is an input to the passenger switch, which then tells the overhead module to fire the lock or unlock relays. The overhead module also has CCD bus lines, this is the nearest place to the lock switch that has both points in common (and probably the only place for that matter)

The CCD lines in the overhead module are purple/brown and white/black on pins 6 and 12 respectively. The unlock relay control is dark blue on pin 5. Hmmm, adjacent pins.

If it is the overhead. Unplug it and see if the code goes away.

JJacobs said:

OK, I told you on the CO thread I would look into this a little. It seems the driver's switch is an input to the passenger switch, which then tells the overhead module to fire the lock or unlock relays. The overhead module also has CCD bus lines, this is the nearest place to the lock switch that has both points in common (and probably the only place for that matter)

The CCD lines in the overhead module are purple/brown and white/black on pins 6 and 12 respectively. The unlock relay control is dark blue on pin 5. Hmmm, adjacent pins.

Click to expand...

Thanks! Ill be checking that out tomarrow. The door harness looks ok, I pulled the whole thing out on the bench and tested the ohms on each wire and they all read zero.

One thing I did notice while running circles around the jeep was that the wires from the rear hatch into the roof have broken insulation and bare wire. Could this be a contributing factor?

if any of them are bus wires yes. Not sure if rear hatch has power locks never owned a XJ with power locks. But if the rear hatch has a power lock definatly could cause a problem.

Beezle said:

Thanks! Ill be checking that out tomarrow. The door harness looks ok, I pulled the whole thing out on the bench and tested the ohms on each wire and they all read zero.

One thing I did notice while running circles around the jeep was that the wires from the rear hatch into the roof have broken insulation and bare wire. Could this be a contributing factor?

Click to expand...

It sure could be the problem. I gotta say that's a weird one, hope you get it sorted.

Thanks guys! I simply took the glove box off unplugged the overhead console and BAM no codes, no airbag light, all gauges work!

That P1698 code sure can be a broad spectrum of things going on.

Thanks for all the help! I hope this helps other people out because all the threads I've seen for the P1698 code have little to no conclusion to them.

Next up is testing wires to see what needs fixed so I can use my console again.

Ill keep updateing.

Well, found lots of corrision on the circuit board for the keyless entry inside the OHC. Sprayed it down with electric cleaner and scraped some off with my fingernail and now everything works again!

Cool!