Cranks, no start.. P1694

Hello all, new here! This may be a long post by will try to include as much detail as possible, I am stumped.

98 Cherokee, 4wd, 4.0l auto with 140k.

Symptoms: Cranks, but no fuel or spark. E-fan is on when key is on. No guages, but odo and engine lights will come on initially. Throwing code P1694.

What I have tried so far: Checked all fuses and relays. Cleaned all fuses with wire brush.
Cleaned all grounds I could find with brush and brake cleaner. (1 near battery, 2 by coil, 1 by dipstick, 1 by alt. 1 from body to block, 2 by computer.)
Unplugged and cleaned the three plugs going to computer.
Verified fuse blocks have power.
Replaced CPS. (That was fun)
Unplugged cps, no change in instrument gauges.
Unplugged the various sensors for motor one at a time, no change in instrument guages.
Crawled under and inspected all the wires I can see, took apart column and kick panels and inspected all wires. Can't see any damaged wires. (Besides some coming from driver door, they have been that way for years, speaker and door lock wires)
Tested data link connector. All pins showing 2.49ish volts(Using pin 5 as ground), pin 3+11 showing 60ohms with battery cable off.

At this point I'm not sure what to try next. Computer may be bad? Missed a ground somewhere?

Any thoughts or tips are greatly appreciated, thanks!

Did you install a genuine Jeep CPS ? Most auto parts stores sell cheap crappy Chinese made parts, some that even come with a " Lifetime Warranty". These parts are poorly manufactured and/or made from inferior materials. They are often out of specification, or even failed, right out of the box. The ones that are not faulty many times will have a short service life before they fail. Always buy top quality replacement parts and genuine Jeep engine sensors. Numerous threads detail long and frustrating searches for a "problem" that ended up being cured simply with genuine Jeep repair parts.

Cheap parts are cheap for a reason.




P1694 Fault In Companion Module. No CCD/J1850 bus messages received at the power train control module (PCM) from the AisinWarner Transmission Control Module (TCM).

P1694 will set if no CCd bus messages are received from PCM for 20 seconds or invalid messages are received for 20 seconds.

Possible Causes
- Faulty Crankshaft Position Sensor.
- Faulty TCM.
- CCD Bus (-) circuit open between PCM and TCM.
- CCD Bus (+) circuit open between PCM and TCM.
- Transmission CCD bus wiring damaged
- CCD Bus (-) circuit open between PCM and TCM.



In the past there have been reports that the Transmission Control Module (TCM) failures and Remote Keyless Entry (RKE) module failures have caused similar symptoms and faults. Note that the RKE module is on the CCD Bus. Try unplugging the RKE module and try unplugging the TCM and see if the NoBus message goes away and all gauges work. If so, replace the TCM or RKE.

You should also at the minimum unplug the drivers door wire harness in case there is a 12 volt short circuit to ground. The e-fan turning ON with the key suggests a short circuit.

Engine sensor wire harness/wire plug issues, a faulty CPS, or a faulty TCM should be the first suspects for a P1694.


Additional reading >> http://www.naxja.org/forum/showthread.php?t=63167

Thank you. No, the CPS was a "higher priced" option from AutoZone. I can test the resistance and see if it checks out or just buy a Mopar one?

I don't think it has a remote keyless entry, but if so where would the RKE module be located?

I'll try unplugging the TCM and door harness and see if that makes a difference tonight.

Update, spent a few hrs last night unplugging various connectors and testing pins in the fuse box under the hood. Turns out a few of the wires going to the fuel pump were chewed through (right above rear axle) and this in turn partially damaged the fuel pump fuse. Fixed the wires and replaced fuse, and boom, gauges returned and E-fan finally turned off with key on. Jeep now runs as it should. Crazy how a few damaged wires can cause so many other issues.