MRRYDER

Recently my 1999 Jeep Cherokee quit running. First time ever. Display read NO BUS.I found a 15 amp fuse blown in the Electrical Power Distribution box under the hood. I replaced it and cleared the CEL with my scan tool.Ran great for about a week and then last night happened again and blew 3 fuses trying to limp back home. Today I put a 15 amp circuit breaker in to help me try to find issue. Wiggled wiring harnesses and looked for wire chafing but no obvious problems found.Cleared CEL and parked.Was running CEL not on. Seems to happen when vehicle is warmed up. When problem occurs I get a fault code of P01695. Anyone out there have any answers as to what may be the issue. Thanks.

Bustedback

Check the wiring to the O2 sensors and make sure they are not grounding out on the exhaust.

MRRYDER

Thanks for your response I will check tomorrow and get back to you.

CCKen

Can you describe what fuse it was. Which fuse?

tjwalker

I do not see a P01695 in the OBDII codes. Are you sure that is the code?

And yes, you must identify the circuit for the fuse that is blowing and then perform a comprehensive search for a wiring issue along that circuit.

MRRYDER

Fuse was not labeled in the PDM box lid.But if you pull it engine will only crank and not start.And dash display will read NO BUS.

MRRYDER

I am picking up a Chilton manaual for the Jeep that I have on hold at the library.I am pretty sure that was the code.My scan tool said code not recognized the first time it happened last week. I will check again tomorrow. Thanks for your reply.

MRRYDER

Thanks for your reply.

CCKen

Here'sa a drawing of the 1999 XJ PDC. Can you identify which fuse it is by its "F" number; example "F16".

CCKen

Code P1695 is "No CCD/J1850 Message From Body Control Module". In that the XJ doesn't have a "Body Control Module" (at least I haven't found one), this may be for a different configuration XJ, unless it refers to a module other than the PCM or TCM. If you re-scan you may find a P1694 code, which is common. The (M) means the CEL is illuminated for this DTC.

This is from Section 25 of the 99 FSM:

P1694 (M) No CCD Messages received from ECM - Bus communication failure to PCM.

P1695 No CCD/J1850 Message From Body Control Module - No CCD/J1850 messages received from the body control module.

Here's a schematic of the DLC and the modules on the CCD Bus:

MRRYDER

Thanks for your reply.My vehicle is a 1999 Jeep Cherokee Classic with a 4.0L engine.Do you have any info on that? Thanks again.

tjwalker

What Ken posted IS from the 99 factory service manual so it is exactly what you have.

MRRYDER

Yes Ken is correct.I just checked.Just looked different in picture and I do not have some of the optional relays.The fuse that keeps blowing is F22.

CCKen

F22 is the fuel pump power fuse. Batt power from that fuse goes to the fuel pump relay, and when the PCM provides a ground to the coil of the FP relay it pulls the relay contacts closed and power from that fuse goes to the fuel pump module. Make sense?

Its obviously a 15 Amp fuse. The maximum draw from a healthy fuel pump is 10 Amps (this is a test of the fuel pump in the FSM). It could be a bad fuel pump drawing in excess of 15 Amps, a bad fuel pump relay, or bad wiring to, or at the pump connector.

I guess you could start downstream and disconnect the fuel pump at its connector, near the fuel tank. If the fuse still blows move up to the relay - remove the fuel pump relay and set it aside, remove the Radiator Fan relay and plug it into the fuel pump relay socket, now see if it blows the fuse. If it still blows the fuse it's time to get the Ohmmeter out and check the wiring from the FP relay socket to the fuel pump connector to see if the power wire is shorted to ground.

I'll help you with this later...my PC just went nuts and I need to shut down.

MRRYDER

Thanks for the great info.I'll do some tests tomorrow.Hope you PC problems get resolved.