Electrical issue

[Timothy James]

2005 Liberty Sport, 3.7, 4x4

Hey guys and gals, I have a strange electrical issue and am looking to be pointed in the right direction.

The problem: Circuit 9 controls the RIGHT side marker lights and instrument cluster lamps. It developed a dead short when I hit a pothole (or two) last winter. When I plug in a fuse and turn on the lights, it blows instantly.

What I have done: Removed a dodgy remote starter; Disconnected right taillight, marker light and parking light and tested each time; Checked all fuses and relays,replaced relay with a known working one. Tried just removing the cluster lamps and testing again, still blows fuse. When I disconnected the instrument cluster entirely and tested, the problem went away.

My question is: Should I take this to mean the instrument cluster is defective and should be replaced? Or do I need to do more diagnosticating?

Thanks in advance.

 

[Billwill]

I do not follow you as regards "Circuit 9"

Are you using the 2005 Jeep KJ Service Manuals as below?

www.colorado4wheel.com/manuals/Jeep/KJ/

Section 8W has the wiring diagrams.

Work from these diagrams so that I...and the other Experts here...can assist you!

So which fuse # is blowing...under the hood or inside the cabin?

 

[Timothy James]

Fuse #9 on the fuse block inside the car will blow instantly whenever the headlights are turned on. When I completely disconnect the connector at the instrument panel, everything works fine.

 

[daves06lrenegade]

replace the #9 fuse with a brake lamp that is in a socket with two wires... the "short" in that circuit will allow the lamp to light until you find/remove the short in the circuit... There will be no fuse to blow only a lamp that is lit until you find where the short is... If the instrument cluster IS bad then the lamp WILL go out when the cluster is disconnected...

 

[Billwill]

This is going to be a difficult short to find.....that circuit goes all over the place via various splices!

Start on page 8W-50-8 of the Service Manual...you will see your Fuse #9 there feeding various lamps via the White/Orange stripe wire.

It goes off to pages 8W-12-15, 8W-12-16 and so on....8W-12-15 is where it goes into the Cluster...if you cut that section of wire Off and the fuse does not blow then it would appear that the Cluster is faulty!

Pull out all the lamps in this White/Orange circuit so that the circuit should be hanging in space....you should not read any continuity of this circuity to Ground via your Multi meter if the lamps have been removed and the Cluster is unplugged.

You should see if you can find a DC 10 Amp Circuit Breaker to replace fuse #9 with so you can stop using up fuses or try a lamp in that position as suggested.

You will need to cut off this White/Orange wire at various branches to see which branch has the short in it...pulling Connector C109 apart will cut off some of the routes...location of Connectors is shown at the end of the index page.

You will probably end up finding one route of this wire that is causing the problem...probably the lead is shorting to chassis somewhere....if you cannot physically see the short you will need to cut off that section of wire at both ends and replace it with a new one!

 

[Timothy James]

Thanks for all the input and advice; I have determined my problem is in the instrument cluster itself. Using the "leave the circuit hanging in space" and plugging a test light into the fuse holder (don't know why I never learned that one!) method, I was able to eliminate everything but the cluster. Now I need to find a replacement...

Again, thanks for all the help.

 

[Billwill]

Weird that you hit a bump and the Cluster fails.

You may as well open it up and see if any obvious problem is evident.

Make sure you get the correct one for your model Jeep from a Breaker Yard.

I am not sure if the mileage of the new cluster has to be programmed into the PCM

 

[Timothy James]

Weird that you hit a bump and the Cluster fails.

You may as well open it up and see if any obvious problem is evident.

Make sure you get the correct one for your model Jeep from a Breaker Yard.

I am not sure if the mileage of the new cluster has to be programmed into the PCM

Funny you should mention opening it up. I did just that and saw nothing obvious. Resistors all checked out fine. Using the pinout on 8W-80-75, one side of the lighting circuit is on pin 1 (Fused B+) and the other is on pin 12 (Fused ignition switch output). Nothing on 19 or 20 which seems more obvious. Anyways, that is the limit of my patience for this at the moment. I may revisit it later.

Again, thanks for all the help.

 

[Timothy James]

Well, guys and gals - after almost a year of banging my head on the wall, my problem has finally been solved! It was indeed one of the cluster lamps causing the problem. It had somehow dislodged from the plastic base, and wedged itself into a position to cause a dead short. I removed the cluster (yet again) and removed all the bulbs. The culprit fell apart in my hand. Replaced a bulb, tested the lights, lather rinse repeat for all the remaining bulbs and now everything is good. Thanks for all the advice and ideas. I will definitely re-use the plug-a-light-bulb-into-the-fuse-holder as a way to begin diagnostics...