Hello all,
This is my first post here, and I'm hoping someone can help me with a problem. A few days ago, the instrument cluster and climate control in our 2000 Grand Caravan stopped working all at the same time. The temp. gauge, speedometer, odometer, and gas gauge are all not working. However, the rpm gauge IS still working. Also, none of the buttons on our climate control panel are working. The fan will turn on and blow, but I can't do anything to adjust the temp. of the air coming out. No a/c or heat. Also, the upper display in the center, above the windshield (that displays outside temp, DTE, mileage, etc) stopped working at the same time everything else did. I read about some similar problems on this forum, and many suggested changing the IOD fuse, which we did. Nothing. So we changed the entire fuse box. Still nothing. Others have suggested a soldering problem behind the cluster, so we took it out, and everything appears to be fine. We're still working on it. We're going to try replacing the cluster altogether, but if that doesn't work, what would you suggest? Also, would a problem with the instrument cluster affect the climate control as well? I'd love to hear all your input.
Thanks!

 

I should also add that we took the vehicle to Auto Zone and had them attach their scanner to see if they could diagnose the problem, and not a single code showed up.

 

Did you read about a melted HVAC control panel connector killing the cluster? Not as common as the cluster solder joint issue but it does happen. The connector melts, usually caused by a blower motor drawing too much current, and pulls the pins breaking contact. Worth a look.

BTW - Just looking at the cluster connector isn't going to do the job. The cracks can be tiny, barely visible. It's always best to reflow the solder on each contact regardless of how good it looks.

AutoZone? If all they used was a typical engine code scanner, and that's the usual case, they won't see more than engine codes and the basic data bus codes. Has to be a scanner capable of reading specialized communications codes.

 

Thanks for the input. We'll take a look at the HVAC control panel. We also just replaced the instrument cluster with one we got from the junk yard, and the exact same gauges are still not working, with the tachometer still working, so I'm pretty sure the problem wasn't with the cluster itself. I'll keep posting with updates. Thanks.

 

You have a tough problem with all those failures in different modules.
I don't have the exact manual or diagrams for this year, so I'll have to find one. In the '06 manual I have, there are some fuses that provide power that is common to these modules.
You're going to need some troubleshooting tools, like a 12 volt test light and a multimeter in order to check voltages and connections. A wiring diagram is very helpful, too.
It would have helped if the parts store had found some codes, but easy is not always the most fun.
I would start by verifying that your fuses do, in fact, have voltage going thru them. Some will depend on the ignition switch being on to have voltage. Pay particular attention to fuses 14 and 24.
After that, if the symptoms are unchanged, I would start disconnecting modules one at the time, starting with the temperature control panel, since there is a possibility of a scorched or melted connector.

 

OK, so I have an update on our van. There is a computer/fuse box underneath and to the left of the steering wheel. In this box, there is a fuse marked "rear wiper." This fuse was burned out, and each new fuse we put in immediately burns out as soon as we turn the van on. Today when my husband was working on it, he used a piece of spare wire to create a "bridge," and bypass the fuse. When he did this, and turned the van on, all our instruments started working again. The wire he used overheated and started to smoke after a few seconds, so he turned the van off and removed it, but it at least gave us a clue as to where the problem is. It seems that whatever is causing the fuse to burn out is also preventing our instruments from working. Do any of you have any idea what might be causing this? We've already replaced that entire box, but the same problem keeps happening, and the rear wiper fuse keeps burning out every time we turn the ignition switch. Also, fyi, we checked the hvac control panel, and even replaced it, and nothing happened. We also checked the hvac connections, and couldn't see any evidence of scorching or melting.

 

BTW, We did re-solder the back of the instrument cluster just to be sure, and the problem still persists.

 

If possible, disconnect the rear wiper motor.

 

We did, and it had no effect.

 

Yikes. You've got an odd one. Can I assume that was 20 amp fuse #6 on the junction block under the dash? Wiper system diagrams show it powering the rear wiper motor. Looking at a power distribution diagram that fuse powers the rear wiper motor, BCM, HVAC panel, message center and compass/trip computer. That pretty much lines up with your problems. Might start with disconnecting components on that list you haven't yet. After that it's meter time. Was any work done on the van just prior to this happening?

Need wire diagrams? Send me an email address to send them to via a private message. How? Click Cougar41 at left.

BTW - My diagrams show fuse IDs labeled as numbers not components or systems ( ya, I know - dumb). Those numbers correlate to a list of fuses in your owners manual. Hopefully fuse #6 matches up with the rear wiper motor.