Not the usual gauge cluster issue

[VermontJeep]

I've ruled out all the fixes I can find for my 'Cluster has power but no gauges' issue and am about to hit a wall. Ideas would be appreciated.

The story so far 1999 TJ, Cluster has power, no gauges. Self test (holding down trip meter button) works. Cleaned all contacts VERY carefully multiple times. Swapped in another cluster, no change. Fuse under the hood was blown, replaced. Cluster started showing 'no bus' error.

More testing showed that OBDII port works fine. All data and gauges work. No codes.

+12 Power to pin 16 is present on OBDII port, but not to pin in B connector on cluster. These are the SAME WIRE in the wiring diagram. I run a jumper from the OBDII to the cluster. No Bus error goes away. Still no gauges.

Check grounds. All good (plus, power, illumination lights and self test work, so I know the main circuit is grounded OK). There is nothing else between the power source and the OBDII plug or cluster except the wiring harness, and where it splits between the two. So it must be an open circuit somewhere other than in the power. Any ideas of specifically what pin I may be looking for? At this point, tearing the whole thing apart to get at the harness under the wiper motor is looking like a pain and I'd love to just be able to run a new wire or 2 if I could!

Thanks. I'm about to tear my remaining hair out over this one!

 

[Rubicon88]

"All data and gauges work"

But your gauges aren't working?
Explain

 

[VermontJeep]

"All data and gauges work"

But your gauges aren't working?
Explain

Maybe it wasn't clear. All the gauges work as in " I can see the data from the gauges through a scanner at the OBDII port" so I know the sensors and wiring and computer are OK, as well as wiring as far as the OBDII port.

That pretty much leaves it down to a wiring issue between there and the cluster. But after checking the +12 (and fixing it) I don't know what the next likely thing is. I've never traced a computer signal on my meter so don't even know what I'm looking for.

 

[qslim]

I've ruled out all the fixes I can find for my 'Cluster has power but no gauges' issue and am about to hit a wall. Ideas would be appreciated.

The story so far 1999 TJ, Cluster has power, no gauges. Self test (holding down trip meter button) works. Cleaned all contacts VERY carefully multiple times. Swapped in another cluster, no change. Fuse under the hood was blown, replaced. Cluster started showing 'no bus' error.

More testing showed that OBDII port works fine. All data and gauges work. No codes.

+12 Power to pin 16 is present on OBDII port, but not to pin in B connector on cluster. These are the SAME WIRE in the wiring diagram. I run a jumper from the OBDII to the cluster. No Bus error goes away. Still no gauges.

Check grounds. All good (plus, power, illumination lights and self test work, so I know the main circuit is grounded OK). There is nothing else between the power source and the OBDII plug or cluster except the wiring harness, and where it splits between the two. So it must be an open circuit somewhere other than in the power. Any ideas of specifically what pin I may be looking for? At this point, tearing the whole thing apart to get at the harness under the wiper motor is looking like a pain and I'd love to just be able to run a new wire or 2 if I could!

Thanks. I'm about to tear my remaining hair out over this one!

What wiring diagram are you looking at? I'm in the FSM and I don't see any lettered pins on the instrument cluster. Looks like B+ is fed to C2 pin 9 and ignition switch output is C2 pin 8.

 

[glowell222]

Everything was working before? Has something changed and then the gauges stopped working? Your gauge swap was with a known good set of gauges? Any idea what caused the blown fuse?

 

[VermontJeep]

Everything was working before? Has something changed and then the gauges stopped working? Your gauge swap was with a known good set of gauges? Any idea what caused the blown fuse?

I just bought the jeep, so don't know the history of the problem. The seller said that when it stopped working orignially, he could sometimes get it going by banging on the top of the dash. The swap was from my previous daily driver which I'm now using for parts and does work. I put the cluster from this jeep into my parts jeep and it works. So 100% not a cluster problem. Don't know what caused the blown fuse. I'm beginning to suspect that this issue may be one reason why the kid was selling it. No gauges, no inspection sticker in my state.

 

[VermontJeep]

What wiring diagram are you looking at? I'm in the FSM and I don't see any lettered pins on the instrument cluster. Looks like B+ is fed to C2 pin 9 and ignition switch output is C2 pin 8.

B1 and B2 on the console plug are voltage for the data link connector. They go to both the console and pins on the OBDII port.

http://www.autolib.diakom.ru/CAR/Jeep/1997/Wrangler/SYSTEM WIRING DIAGRAMS/13892.pdf
The port had the voltage, but the Console did not. I fixed it by running a jumper from the OBD port to the back of the console (fixed the No Bus error).

The fuse 17 'always on' which went to A9 behind the console was blown. I replaced that. It has not blown again. I do have voltage now at the console on A9.

Then if you look at http://www.autolib.diakom.ru/CAR/Jeep/1997/Wrangler/SYSTEM WIRING DIAGRAMS/13877.pdf you'll see that a lot of the data/power lines go to the console and the OBDII port, they just split. So since the port works, I must have an open wire somewhere between the split and the console. I have power now so need to figure out which data wire is the most likely suspect at this point of no gauges work.

Do you know if, where these wires split in the harness, it is a plug? Maybe that plug is just lose/dirty.

 

[VermontJeep]

B1 and B2 on the console plug are voltage for the data link connector. They go to both the console and pins on the OBDII port.

http://www.autolib.diakom.ru/CAR/Jeep/1997/Wrangler/SYSTEM WIRING DIAGRAMS/13892.pdf
The port had the voltage, but the Console did not. I fixed it by running a jumper from the OBD port to the back of the console (fixed the No Bus error).

The fuse 17 'always on' which went to A9 behind the console was blown. I replaced that. It has not blown again. I do have voltage now at the console on A9.

Then if you look at http://www.autolib.diakom.ru/CAR/Jeep/1997/Wrangler/SYSTEM WIRING DIAGRAMS/13877.pdf you'll see that a lot of the data/power lines go to the console and the OBDII port, they just split. So since the port works, I must have an open wire somewhere between the split and the console. I have power now so need to figure out which data wire is the most likely suspect at this point of no gauges work.

Do you know if, where these wires split in the harness, it is a plug? Maybe that plug is just lose/dirty. Its not in a very accessible place.

 

[qslim]

1 and B2 on the console plug are voltage for the data link connector. They go to both the console and pins on the OBDII port.

http://www.autolib.diakom.ru/CAR/Jeep/1997/Wrangler/SYSTEM WIRING DIAGRAMS/13892.pdf

That diagram you linked out is missing intermediary connectors. I didn't bump all the color & pin locations against the factory service manual, but I'd dump that link and get your '99 manual. Section 8W-40 shows the factory wiring for your instrument cluster.

https://wranglertjforum.com/threads...ice-manuals-fsm-technical-documentation.4618/

 

[VermontJeep]

That diagram you linked out is missing intermediary connectors. I didn't bump all the color & pin locations against the factory service manual, but I'd dump that link and get your '99 manual. Section 8W-40 shows the factory wiring for your instrument cluster.

https://wranglertjforum.com/threads...ice-manuals-fsm-technical-documentation.4618/

That manual is going to be a lifesaver (or at least save my sanity), thanks!

 

[qslim]

That manual is going to be a lifesaver (or at least save my sanity), thanks!

Yeah man, I honestly haven't had time to read your original post that thoroughly & bump it against the wiring diagrams like I usually do, but go with the FSM. You might also look in the section that describes the instrument cluster, some sections in the manual have some pretty robust troubleshooting procedures.

 

[mstopher82]

Were you able to come up with a solution to this? I'm having the exact same problem. Gauge test works perfectly every time, OBDII reading fine (speed, RPM, coolant temp) all working on the scanner, all lights working in the cluster but none of the gauges. It's driving me insane. I've put a slight bend in the prongs behind the cluster, cleaned pins, checked fuses ect.

It seems as though the data is just not getting to the cluster.