Jeep Wrangler TJ Full Electric Conversions

Gauge cluster problem

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RcJeep

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Hello all,
I recently bought a 2004 Tj- Runs good no issues there but here is my issue, this was a 4cyl jeep originally with a manual, it is currently a 4.0 automatic, the engine was from a low milage 1999, everything works as is should as far as I can tell running wise, the instrument cluster illuminates check engine, turn signals air bag, but no speedometer, fuel, oil pressure coolant temp. I originally thought this is because it has a 2004 guage cluster, so I purchased a 1999, well the wiring isn't a direct plug in, quick connectors are totally different I'm lost, I could buy a donor cut pig tail from a 1999 yes but then how do I splice everything together and If I was to do this am I doing this the way I should will it now talk to the guages? I appreciate any insight, I would really like to have my guages work.
 
Whoever swapped in the 1999 engine appears to have also swapped in the wiring (including the dash wiring) for the 1999.

That being said, keep the 1999 gauge cluster in there. You're going to have to get out your multimeter and the wiring diagrams in the FSM to figure out why the gauges aren't working. It sounds like maybe the previous owner did a half ass job on the wiring / sensor install.
 
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I’m sure more knowledgeable folks will chime in, but I would start with checking all the pins on the plugs to the cluster to make sure they are all getting the power they are supposed to be.
 
If you're lucky whomever did the swap did everything...gauge cluster...all of the wiring harness...PCM...connected all the grounds.

I have a 1997 4.0. Wrecked the frame and tub. Bought a 2000 frame and tub from a wrecker. It was a 4 cylinder frame. So I moved the motor mounts and everything from the 1997 to the new tub and frame. Zero issues.

My guess is whomever did the swap took shortcuts with the wiring harness.

And that's going to be a tedious problem to track down.

-Mac
 
Thanks for the reply's, however I may of miss typed, the dash wiring is still a 2004 the same with the cluster, I purchased a 1999 cluster not knowing the plug configuration is different.
 
It's not just the plugs, man. Pretty sure the 99 stuff is gonna talk CCD and the 04 is PCI. Even if you lined up the plugs and wiring the 99 PCM is speaking a language your 99 cluster doesn't understand. There are experts here that will correct me if I'm wrong but I think you need a 99 cluster.
 
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Ok, any insight on how I get the pcm to talk the same? I'm mechanical enough to fix the issue but I'm not so handy with electrical
 
What I'm hearing is you probably have a 99 engine. 99 PCM - need to verify this. 2004 dash harness - need to verify this, dash cluster plug is a good clue.

Nothing is working right because it's not going to the right pins or places.

What you might need is a 99 dash harness or a complete 99 harness.

All of this is speculation. Needs verification.

-Mac
 
RcJeep said:
Ok, any insight on how I get the pcm to talk the same? I'm mechanical enough to fix the issue but I'm not so handy with electrical
Click to expand...

A 99 cluster and the wiring to make it work. Don't think the protocol is configurable and you can't put an 04 PCM on a 99 afaik because transmissions and the ignition system is completely different.
 
Yes 99 Engine, 99 PCM, Yes on 2005 Dash wiring since it clips correctly into the 2004 Cluster, I'm assuming the 99 dash cluster will be a complete harness with fuse block ect.. I was hoping that I could buy 99 pig tails that clip in the 99 cluster and have someone advise on repinning. But like I said I'm not great with wiring
 
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RcJeep said:
But like I said I'm not great with wiring
Click to expand...
Wiring is tedious, but not that hard. You would need wiring diagrams for both years. Going one wire at a time, trace each wire from the PCM and figure out what it does. LABEL each wire. Starting at the '99 cluster, figure what every connection, each individual pin needs. LABEL them. Then it's just a matter of connecting each wire together. It won't be easy, but as long as you take your time, and double check your work, it should be possible.
 
I do believe someone put together an AI model of the wiring. You probably could use it to make an exact list of the differences.

-Mac
 
So your saying find each wire and what it does and wire in to 99 pigtails? that i could remove from a junk yard jeep?
 
RcJeep said:
So your saying find each wire and what it does and wire in to 99 pigtails? that i could remove from a junk yard jeep?
Click to expand...

That's one method. The pin outs are different. There are wires running to completely different spots...case in point the headlight multifunction switch vs a seperate headlight switch for the 99.

I would highly suggest getting a 99 dash harness and pulling the dash.

-Mac
 
1. 2004 Black Connector (C1)
With the locking tab facing UP, looking at the back wire side:
  • Pin 5: Black / White wire (Connects to 1999 C2 Pin 8)
  • Pin 7: Gray / Black wire (Connects to 1999 C2 Pin 4)
  • Pin 8: Tan / Black wire (Connects to 1999 C2 Pin 5)
  • Pin 9: Black / Light Blue wire (Connects to 1999 C1 Pin 8)
  • Pin 10: Black / Dark Green wire (Connects to 1999 C2 Pin 7)
  • Pin 11: Pink / Black wire (Connects to 1999 C2 Pin 10)
  • Pin 21: Pink / Yellow wire (Connects to 1999 C1 Pin 4)
  • Pin 22: Orange / Black wire (Connects to 1999 C1 Pin 7)
  • Pin 23: Light Green / Red wire (Connects to 1999 C1 Pin 6)
  • Pin 24: Light Green / Black wire (Connects to 1999 C1 Pin 3)
  • Pin 25: Tan / Red wire (Connects to 1999 C1 Pin 2)
  • Pin 26 (Far Bottom Right): Dark Blue / White wire (Connects to 1999 C1 Pin 1)
2004 Light Gray Connector (C2)
With the locking tab facing UP, looking at the back wire side:
  • Pin 9: Violet / Yellow wire (DO NOT CONNECT - This is the live 2004 PCI Data Bus wire. Tape it off safely.)
  • Pin 13: Red / Black wire (Connects to 1999 C2 Pin 1)
  • Pin 14 (Far Bottom Left): Yellow wire (Connects to 1999 C1 Pin 5)


I found this.
 
So far everything else works, lights, turn signals, radio, hazards, wipers ect.. just no oil pressure, gas, volts, tach and speedometer
 
RcJeep said:
So far everything else works, lights, turn signals, radio, hazards, wipers ect.. just no oil pressure, gas, volts, tach and speedometer
Click to expand...

Is this with the 2004 cluster?

Oil pressure, fuel level, volts, tach, and speedo are all sent from the PCM over the data bus. I also suspect your odometer may be showing "no bus"?

You'll need to take your 2004 harness and repin it into 99 connectors to plug into the 99 cluster, and make sure you get the data bus connected correctly to make those gauges work.
 
The odometer reads fine I've never seen the no bus, I did do a hold the trip in, turn the key diagnostic on the guage and they all functioned i seen a b0 and a b8 pop up. I did try unplugging the air bag silver box under radio on trans tunnel, I unplugged it and got a no bus, plugged it back in and it went away.
 

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