I'm having an intermittent electrical problem with my 2003 3500 with 275,000 miles on it. I'm the original owner. I've been chasing this problem for a while and I need help from someone smarter than me to find the source of the problem and fix it.
It started months ago with temporary and intermittent instrument cluster power loss, or so it seemed. I noticed power would momentarily drop out. Gauges would go to zero and then a ding would be heard as it all powered back up. Initially, it only happened when it was cold/cool. As the truck warmed up, it stopped happening. It happened longer on cold mornings than on warm ones. During the summer, it pretty much stopped happening. When fall came around and temps dropped, it started happening again. A local shop identified the problem as my instrument cluster. P/N no longer available for replacement. I found one of the instrument cluster repair shops and sent the cluster to them for repair. They tested the cluster but couldn't find a specific failure, however, they reflowed all the solder joints that typically cause a problem and it all tested good for them.
I reinstalled the cluster and the problem was still present - No change. The repair shop sent me a list of wire harness pins to test and report voltage values on. Several power leads and ground leads. All tested within specs. However, I'm not sure my meter would catch such a short intermittent power loss. So I uninstalled and sent the cluster back under warranty for more testing and repair. I explained to the repair outlet that it all seemed to be temperature sensitive in nature and would stop once the truck warmed up. They put the instrument cluster in the freezer for a few hours and then retested. They tried other methods to induce the failure but could not cause it to fail. I reinstalled it on return and the problem still persisted.
I've been trying to isolate it and have been doing other trouble shooting. Which has gotten somewhat easier because now the problem persists even when the truck is warm. In the repair manual, in the electrical wiring section 8W-40-11, There is a diagram and it appears that everything in this diagram is potentially affected. At the top it says "Instrument Cluster" and contained within is the Cargo Lamp, Panel Lamps, Courtesy Lamps, Heated Seat Switches, Panel Lamps, Dome Lamp, Glove Box Lamp, Radio, Center High Mount Stop Lamp/Cargo Lamp and A/C - Heater Control. I can confirm that everything listed accept the A/C Heater Control loses power momentarily. And it seems like it might be a capacitor problem because it happens like clockwork every 25 seconds. I have set a lap timer on it and over 10 power loss cycles, they are all within 1/2 second of 25 seconds between power loses. I've attached an image of the page in the wiring diagram manual.
1) It does not seem like a bad ground problem to me.
2) I am not confident the instrument cluster is not the problem. I'm contemplating sourcing another instrument cluster in order to swap out and compare results.
3) I'm not sure my meter would pick up the temporary power loss on any of the wire harness leads. The loss is very shot and the gauges don't even make it to Zero before the power is pack on and things return. It's defiantly momentary.
4) I've looked in the fuse panel and checked all the fuses and cleaned contacts. No change.
5) The engines runs normal and is not affected. The exterior lights are not affected. The power windows and seats are not affected (accept seat heaters). The power outlets in the cab are not affected.
6) The turn signal indicator sound (flasher noise), stops making noise during power loss. But the turn signal light continues to flash. It's just the noise maker that stops.
7) The instrument cluster and other interior elements lose power even when the key is turned on but the truck is not yet started. i.e. while I'm letting the fuel warm up, power is lost intermittently before I turn the key to start position.
If you know how I can find the source of this problem, please let me know. If you know some other tests I can do, please let me know. Any suggestions at all would be appreciated. I'm not a full-time or part-time mechanic, so you might have to dumb it down for me.
It started months ago with temporary and intermittent instrument cluster power loss, or so it seemed. I noticed power would momentarily drop out. Gauges would go to zero and then a ding would be heard as it all powered back up. Initially, it only happened when it was cold/cool. As the truck warmed up, it stopped happening. It happened longer on cold mornings than on warm ones. During the summer, it pretty much stopped happening. When fall came around and temps dropped, it started happening again. A local shop identified the problem as my instrument cluster. P/N no longer available for replacement. I found one of the instrument cluster repair shops and sent the cluster to them for repair. They tested the cluster but couldn't find a specific failure, however, they reflowed all the solder joints that typically cause a problem and it all tested good for them.
I reinstalled the cluster and the problem was still present - No change. The repair shop sent me a list of wire harness pins to test and report voltage values on. Several power leads and ground leads. All tested within specs. However, I'm not sure my meter would catch such a short intermittent power loss. So I uninstalled and sent the cluster back under warranty for more testing and repair. I explained to the repair outlet that it all seemed to be temperature sensitive in nature and would stop once the truck warmed up. They put the instrument cluster in the freezer for a few hours and then retested. They tried other methods to induce the failure but could not cause it to fail. I reinstalled it on return and the problem still persisted.
I've been trying to isolate it and have been doing other trouble shooting. Which has gotten somewhat easier because now the problem persists even when the truck is warm. In the repair manual, in the electrical wiring section 8W-40-11, There is a diagram and it appears that everything in this diagram is potentially affected. At the top it says "Instrument Cluster" and contained within is the Cargo Lamp, Panel Lamps, Courtesy Lamps, Heated Seat Switches, Panel Lamps, Dome Lamp, Glove Box Lamp, Radio, Center High Mount Stop Lamp/Cargo Lamp and A/C - Heater Control. I can confirm that everything listed accept the A/C Heater Control loses power momentarily. And it seems like it might be a capacitor problem because it happens like clockwork every 25 seconds. I have set a lap timer on it and over 10 power loss cycles, they are all within 1/2 second of 25 seconds between power loses. I've attached an image of the page in the wiring diagram manual.
1) It does not seem like a bad ground problem to me.
2) I am not confident the instrument cluster is not the problem. I'm contemplating sourcing another instrument cluster in order to swap out and compare results.
3) I'm not sure my meter would pick up the temporary power loss on any of the wire harness leads. The loss is very shot and the gauges don't even make it to Zero before the power is pack on and things return. It's defiantly momentary.
4) I've looked in the fuse panel and checked all the fuses and cleaned contacts. No change.
5) The engines runs normal and is not affected. The exterior lights are not affected. The power windows and seats are not affected (accept seat heaters). The power outlets in the cab are not affected.
6) The turn signal indicator sound (flasher noise), stops making noise during power loss. But the turn signal light continues to flash. It's just the noise maker that stops.
7) The instrument cluster and other interior elements lose power even when the key is turned on but the truck is not yet started. i.e. while I'm letting the fuel warm up, power is lost intermittently before I turn the key to start position.
If you know how I can find the source of this problem, please let me know. If you know some other tests I can do, please let me know. Any suggestions at all would be appreciated. I'm not a full-time or part-time mechanic, so you might have to dumb it down for me.
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