BomberJeep

I've been troubleshooting my reverse lights for a bit now. After some research I found out that fuse 10 controls it. According to the owners manual fuse 10 should be empty. Also it says fuse 8 should be empty but I'm getting voltage at fuse 8 with the ignition on and the tranny in reverse. If I put a 15a fuse in 10 it pops. Should there be a fuse in spot 8 and if so what size? Any help would be appreciated.

Lowrange2

I'd guess you have a short in that circuit...

Looks like 8 should be empty and 10 should have a 15 amp fuse.



How's the NSS?

BomberJeep

The Nss is clean. I've gone thru it a few times. I can't seem to find the wiring diagram for the Nss. I'm finding it wierd that they worked and it say and all the sudden nothing.

CCKen

Fuse #8 spot should remain empty. Do not use a higher rated fuse in #10 spot to troubleshoot the problem.

My '99 owner's manual shows #10 spot as empty as well, but the wiring diagrams shows fuse 10 (15A) in the Junction Block as powering the Duty Cycle Evap/Purge Solenoid, Radiator Fan Relay (in PDC), AC Compressor Clutch Relay (in PDC), and the reverse contacts in the Transmission Range Sensor (aka NSS). It also powers the Daytime Running Lamp Module (Canadian XJ's) and the Evap Leak Detection Pump (if installed). If fuse 10 is blowing with a 15 Amp fuse in place, there's a dead short somewhere. You could get a hand full of 15 Amp fuses and try eliminating circuits that may be shorted. If you have trouble finding the TRS connector I have a photo I can post that shows its location; let me know if you need it.

Note: The key needs to be in the RUN position to check these circuits.

I think if the Duty Cycle Evap/Purge Solenoid was shorted out causing #10 to blow you would get a CEL (P0443) so leave it until last.

Note: This fuse powers the control coils in these relays, not the power contacts.

Pull the AC Compressor Relay (PDC) and see if the fuse blows.

Pull the Radiator Fan Relay (PDC) and see if the fuse blows.

If you have a Daytime Running Lamp Module, detach the connector from the module and see if the fuse blows.

If you have a Evap Leak Detection Pump, detach the connector from the LDP and see if the fuse blows.

Detach the connector from the Duty Cycle Evap/Purge Solenoid and see if the fuse blows.

If none of these circuits proves to be the source of the short, I would suspect the Transmission Range Sensor (TRS) (aka NSS) circuit. The NSS can be isolated by detaching the TRS connector and see if the fuse blows. The TRS connecor is in the group of three connectors near the tranny dipstick tube. In my '99 it's the grey connector, the other two are black. They are connector C107 and the Transmission Control Assembly (TCA) (solenoids) connector.

Give this a try.

BomberJeep

Thank you for the info. Fwiw my father in law (previous owner) had the ac clutch welded to the pulley. Could that play into this at all if the pump is constantly running?

CCKen

I wouldn't think so.

If the fuse is constantly blowing there's a short in one of the circuits I mentioned. If yo want, you could pull the AC Compressor Relay first and see if that stops the fuse from blowing. If not, move on to the next circuit.

BomberJeep

I'm not sure exactly what happened or what fixed it but they started working again. Hmm. Guess they will blow again but hey they worked long enough to get an inspection.