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I am not sure if my problem relates specifically to the dash or if it a bigger issue with the cars computer. Yesterday, the gas and temperature needles rose all the way to full and hot, the speedometer stopped moving altogether and the rpm needle started bouncing erratically. (The gauges on the dash are all needles, except for the trip set and odometer which are digital… the trip sets seem to be correct, but the odometer is reading 9999999) I drove the car and everything was operating normally except for the gauges and I am unsure as to whether there is a problem with the instrument panel or the cars computer.
I disconnected the battery for about an hour and then upon reconnecting, all had returned to normal… This lasted for about 2 short drives and now the dash is behaving in the same fashion.
I am unsure as to what troubleshooting steps to take at this point and was wondering if anyone had any experience solving any similar problem.
Also, if I need to change the computer, does anyone know if this is a big deal… or easy to do?
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could be a issue with the instroment cluster too but that just sounds bonkers, my first suggestion, check the battery and its voltage which should be roughly close too 12.6V and should not drop below 9.6V during starting, a bad battery with low voltage can cause all sorts of wonky things, check the connections too the battery next, if they are corroded clean the connections make sure everything is in order and nice and snug, then if that doesn’t work my suggestion is plug a scan tool in and see if you get any codes because sometimes if there is a Error with the PCM the PCM will store a code saying so. just had a issue with my cars PCM not too long ago, it would randomly shut the car off mid driving, and tell me the Electronic throttle control was my issue on the heads up display… after a while it finally threw a code for a PCM internal fault.
check this too
http://www.ericthecarguy.com/faq/solving-automotive-electrical-problems
There’s one or two big plugs on the back of the instrument cluster. I’m thinking maybe a plug is starting to juggle loose. If you wish to check, disconnect the battery first.
Thanks… I will check out the voltage on the battery tonight. I am a little suspecting of the connections to ground throughout the vehicle as sometimes it “grounds out” when starting… meaning I have to back off the key and try again to turn the ignition over… but the connections to the battery itself seem good. I have a lower end scan tool and right now the engine light if off… I had cleared a couple of codes about 200 miles ago which were (I think) related to some exhaust work that had been done around the braided pipe near the O2 sensor… but that has stayed off since resetting.
Thanks so much for your time and thought into the matter.
– Matt
Thanks for your thoughts and help… I was considering loose wires, and did a little (shall we say..”tapping” around the dash area)… but no change… my concern is what is involved in actually getting at the back of that instrument panel… Doesn’t look like its going to be quick and easy….
– Matt
Yeah, it used to be cars had lots of grounds and few accessories. Now, the opposite. So, looking for the grounds and polishing them with sandpaper can often cure mysterious problems.
thanks…. after looking at ETCG video on electrical troubleshooting, I think I am going to start with a simple battery cable clean up… even though they looked alright… also he mentions in the video http://www.bbbind.com/ which happened to have a bunch of wiring diagrams for my vehicle. Going to check it out this evening after work.. thanks again for the help..
– Matt
what the link says that collage man has shared with you is Vehicle speed sensor could be causing this issue with your speedometer, possibly also your Odometer, but i am still suspicious about how the fuel gauge acts, my dads truck had a issue with the vehicle speed sensor and his speedo just flat dropped and would not read any speed occasionally turning back on for most of the ride, with my car when they go bad the speedo can go all over the place, in both cases with a bad vehcile speed sensor usually with a automatic transmission odd shifting results sometimes the car will put itself into a limp in mode and stick in 2nd gear, because the Vehicle speed sensor is also responsible for telling the PCM how fast your car is gong, and with the throttle position sensor and a few other sensors, gives imputs too tell your transmission when too shift, if it goes bad i believe should experience erratic shifts or it holding in a particular gear.
the fact your fuel gauge and temp gauge reads full leads me too believe you have other issues, you can chech the vehicle speed sensor, but still i would check battery, its connections, grounds, and codes first, because something is making the fuel and temp gauge act up.
Thanks… yes, still going to start with the basics… like we all seem to agree.. the problem is more that just one gauge … so could be something more general… I will report the finding as they arise… stuck at work though until 5pm
Thanks again….– Matt
Well I checked all the vehicle’s fuses and I did the battery terminal cleanup and cleaned up the battery’s main ground to the engine and upon reconnecting the dash acted normal… after a few restarts though, the problem returned. So I decided to start pulling out the dash… (I did this with the engine running to see if there were any loose wire issues…) At one point in the process, the panel went back to normal… so I screwed it back in and at some point it went back to the problem again….
So I pulled it out again and spent some time pulling out the plugs from the back and re-seating….However, the problem remained….
Based on the facts, which I will restate here in a second.. I think the dash itself may be the problem… I would love to know if anyone agrees or disagrees with this logic….
Here are the facts (of the dash symptoms): [Assume the dash is acting normally and about to exhibit the problem….] When I turn the key to ACC. the temp needle and the fuel gauge needle go straight to “all the way” hot and “all the way” full…. The Odometer says 999999 and when I start the engine, the speedometer does not work at all and the rpm needle bounces erratically around 1000 rpms.
When I turn the key back to off… the temp & rpm needles will drop (like they normally should), but the fuel one remains at “all the way” full…. Even when I disconnected all the plugs from the back of the dash, the fuel gauge still remained at “all the way” full.
So logically I am inclined to think that there must be a problem with the dash itself. I am thinking of changing it if I can pick one up at a junkyard… however, I am not sure as to how to change the connection on the back for the speedometer (it is not a simple plug like all the rest of the connections) Anyone have any experience with that? I am thinking that I may have to pop off the front plastic and detach the connection with the 2 little screws that are on either side on the needle in the front….
Anyway…. in the process I tried to take some (very amateur) video and some pictures… If anyone is interested to see any of it, please let me know and I will try an post it on youtube. Thanks all for listening and the thoughts and advise….
– Matt
its sounding like the instrument cluster too, but i hate throwing parts at things as my experiences with that have been very bad with cars these days, i am surly thinking since you have cleaned all your grounds and verified that battery voltage is in that it is the only thing that makes sense, bad wiring would cause a gauge not too work, the gauges are doing something, just not what they are supposed too be doing, any other solution would be your fuel sending units level sensor is faulty, with your vehicle speed sensor, and your coolant temperature sensor, and your tach signals are erritac, i find it highly unlikely too have all these failures at once.
lets see the video, and i say if you can pick a dash up for a decent price lets change them out and see what happens, if you do change the instrument cluster be sure its a good one from someone reputable, because if this is a pattern failure for this car you may end up with the same issue down the road, get a good replacement.
I did check the voltage… was reading 12.47 so just good enough really…. I looked all over for any ground points to clean… I have a good friend who is a mechanic so I think I will give him a call as well… see what he thinks… As for the part… I spoke to a junkyard and I can pick one up for about 75 bucks…
But I agree with you in that I would not have all these failures at once, and bad wires would more likely mean the gauges would not work at all… So after checking battery voltage, fuses and the grounds… that leaves the dash or the car’s computer itself… But I figure that if there was trouble with the computer itself… I would see other signs too…
Last night after putting all the intake assembly back together, I accidentally forgot to plug in the mass airflow sensor… I started the engine and it threw a P100 right off the bat… I plugged it in and reset the code and no problem since…. So I would take that as an indication that the computer is operating in a normal fashion….
Will try and piece some of these video clips together… I am ultimately “terrible” as doing videos… heck I am a total amateur at the repair work itself… trying to manage taking video as well… forget it… but I will try and post something…
I was pleasantly surprised at how easy it was to actually get at the instrument panel and take it out…
Like I said before though.. I wasn’t able to disconnect the speedometer connection though…. so still have to figure that one out…..
Thanks again for the thoughts and discussion
– Matt
I spoke with my mechanic. He said that it is likely a diode gone bad in the dash itself. (He said that when they send them out to be rebuilt, it is $500 and up)… so the 75 dollar one from the junkyard is a home run… so I just ordered it… they are going to ship it out to me today and I should have it by Thursday. I took a short video driving in to work this morning that shows what is happening with the panel… have put it up on youtube if you (or anyone for that matter) want to see the symptom… here is the link….
Thanks again for listening
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