Repair Topics / Gauges

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Car Gauges Question and Answer

Question:  2003 Dodge Grand Caravan Sport mileage: 43,000. Our van would not start after the kids ran the battery down listening to the radio. The van was jump started. The jumper cables were attached to the dead battery first then to the booster battery of a car that was running. After the van was started the speedometer and tachometer did not work. They still do not work after multiple starts. I looked at the fuse box and none of the fuses are labeled for those two items. It seems that everything else electrically is working. Did a relay/fuse burn out because of the jump start? If so, which one do I replace. Is there something possibly more serious? If you have any ideas please let me know. Thank you.

Answer:  When your Caravan was jump-started, a voltage spike may have damaged the alternator.  If it is a fuse, you will need to check them all to determine which ones to replace.  Also check the vehicle speed sensor to be sure that it is sending a signal to the speedometer. 

Question: 1997 Plymouth Voyager mileage: 140,000. My Plymouth Voyager has developed an intermittent problem. While driving suddenly the speedometer, tach and other gauges flip out and bounce all over the scale. The electric door looks pop up and down. It happens frequently but intermittently. It's funny but, I'd swear that the action gets more fast and furious when I accelerate during these episodes. Can you be as specific as you can because I'm the poor sap that has to fix this?

Answer: The first thing we would check is the body control module. Then check for loose or poor ground connections. Lastly, check the main power distribution box.

Question: 1999 Pontiac Grand Am mileage: 145,000 The coolant temperature light and fuel empty light are stuck "on" yet both the temperature gauge and the fuel gauge work perfectly. The cooling system seems work fine, i.e. the fans switch on and off and regulate temperature to the middle of the gauge. In the wiring diagram found in the Haynes manual there seems to be a dark green wire that goes from the ignition switch to both of these circuits. Any ideas? Is this a common problem? In poking around I did notice that some of the contacts on the ignition switch were at 14v. This surprised me.

Answer: It appears that the warning lamp illumination module has failed. Replacing it should fix your problem. The problem is not a common one to our knowledge.

Question: 2004 A4 Audi mileage: 43,900. I just bought a Audi here in Prague Czech Republic. It doesn't have an owner's manual and everything is in German. After I got it home and it sat for a day, I it started it and the battery light and engine temperature light stays on after ignition. The strange thing is the two lights get brighter only when I'm accelerating. When I shift gears the lights would fade until I put my foot back onto the gas pedal. I've checked the battery, it's almost like new, and the engine doesn't seem to be overheating. I thought it may be the alternator, but even that looks good. Someone who also owns an Audi suggested that it may be the relay, but for the life of me, I can't find where the relays are. I would take it to a repair shop but here in Prague they charge you an arm and leg just to look at the vehicle, let alone fix it, besides, it's a standard and I need both arms and legs to drive it. Can you guys point me some sort of direction of what to look for or what to ask for. Bernie

Answer: Without seeing your car and doing some testing, we have to do a little guessing. First, we would test the alternator and make sure that it is putting out 14 to 14� volts. If the voltage output is okay, we would still suspect the alternator because a diode that is failing will cause the battery light to come on even though the charging is okay.

Question: 2003 Ford F-150 mileage: 38,000. My fuel gauge is not working properly. It will show from empty to half full even when talk is full of fuel. Is the problem with the fuel gauge or is it in the sending unit? My friend said it is the battery. He said I should pick up the battery and put it into a newer truck. (Laughing out loud!!!) All joking aside, thanks for any help you can give me. Aloha from Hawaii, Danny

Answer: Try unhooking the wire from the sending unit in the gas tank and with the key on, read the fuel gauge. It should read empty. Now, ground the sending unit wire and it should read full. If this is the case, your sending unit needs replacing. If not, it is the gas gauge sender.

Question: 1999 Chevy S10 mileage: 136,000. The fuel gauge reads full, empty, or basically, whatever it wants to. It moves very slowly during start-ups and usually registers completely opposite of what I believe it should read. What is the most likely problem? Can I free up the sending unit (float?), or should I replace it. Does the entire unit (fuel pump, filter, sending unit float) come as one piece?

Answer: The sending unit in the fuel tank is probably faulty. It is replaced with the fuel pump.

Question: 2002 Ford F-150 mileage: 51,000. The temperature gauge in my truck never seems to move much (it sits on the cold mark nearly always) no matter how much I drive. Even with the a/c on a hot day, it only moves up a fraction of an inch. Could it be my thermostat?

Answer: From what you have explained, you probably have a faulty temperature gauge or sending unit. If the Thermostat was the culprit and stuck in the open position your car would register normal or above normal on your gauge when driven on a hot day for long distances.

Question: 1999 Plymouth Grand Voyager mileage: 116,300. My compass/trip computer quit working. First, it started intermittently then went completely dead. Is there a relay that powers it? If so, where is it located?

Answer: There is no relay for your trip compute. Try checking all of the fuses. If they all check okay, then you may have to replace the body computer.

Question: 2002 Dodge Intrepid mileage: 65,000. The gauges have been working on and off for about three months. The dealer's mechanics have not been able to find the problem as the car is in the shop for the third time. The problem seems to get worse over time. If I pull the battery cable, and replace after a couple hours, the problem will go away for a while. I have even seen the gauges pegged when started, and come to life after about ten seconds. They have replaced the module on the trans, and think it may be another. At about $160/parts per try, I am getting desperate. The problem will occur when the car is cold or hot, sometimes the ignition has to be turned on and off for over twenty cycles before the gauges will work. The air bag light will also come on whether the gauges work or not.

Answer: Without seeing your car, it is impossible for us to help you here. Intermittent electrical problems are the most difficult to find. Your gauges have circuit boards with hundreds of solder joints. If there is just one joint that has moved and cracked the solder, it could cause the problem you described. In addition, an improper ground connection anywhere in the system could be the culprit. We wish we could help you more.

Follow-up: Sounds a shorted wire in the ignition harness. Check the harness for external damage. Repair as needed.

Question: 2002 GMC Sierra 1500 mileage: 75,000.  Sometimes when I start the truck,  the tach, speedometer, & gear indicator light will not work.   When this happens, throttle response is extremely poor & sluggish.  Also, when shifting from reverse to forward gear, it has a very hard shift, I also don't think it's going into overdrive.  Any help would be greatly appreciated, Chris

Answer: Check the ignition switch one of the contacts in the switch may not be functioning properly. Or it could be a body control relay.

Question: 1998 Chevrolet Camaro mileage: 110,000.  My car doesn't have much for instrumentation, besides the speedometer and fuel gauge it only has "idiot lights". They don't tell me what my oil pressure is and how hot my car is running.  What would I have to do in order to install one of those three gauge sets (oil/water temp/amps) into my car?

Answer: You will need a set of aftermarket gauges and once you purchase, follow the instructions that come with the gauges for installation.

Question: 2001 Buick Century mileage: 99,000.  I am looking for a part in my Buick Regale’s digital dashboard.  The odometer won't work and I think the problem is in the 8-pin IC that drives the stepper motor in the odometer.  Who would sell the IC?  EGC and NTE don't have the cross-reference.  # on the IC is 9863B  & C59028H.

Answer: We always replace the instrument cluster rather than trying to repair the digital dash.  The reason for this is that usually the failure of one component is caused by another faulty component and a week later, it will fail again.

Question: 2001 Chevy S10 mileage: 98,006.  I was driving down the road all of my gauges started going crazy.  After a few minutes everything went dead, my lights, windshield wipers, gauges, everything.  But the truck still runs.  It loses some power.  When you turn it off, then turn it back on the battery gauge reads about 9.  It is a brand new battery and alternator.  What do I need to do?  

Answer: From what you tell us, it sounds like you may be having trouble with your charging system.  Have your battery load tested and check the alternator output for voltage and amperage.

Question: 1999 Chevrolet Suburban mileage: 134,000.  My dash lights do not work nor do the speedometer and turn signal.  I have checked the car manual and cannot find a cause.  The fuse box on the side panel says that it controls other lights but all those work, except for the three above.  Any suggestions - appreciate your help. 

Answer:   Check for 12-volts that feeds the fuse panel, especially the connectors that are energized by the ignition switch.

Question: 2002 Honda Accord, miles: 60,000.  All the gauges on the dash board quit no rpm, gas, speed, temp it’s been at the repair shop for a week they replaced the body module and the transmission module they can’t seem to find an answer.

Answer:   Check for 12-volt power to the control modules and make sure they are properly grounded.  If this checks out okay, the dash cluster is likely your problem.

Question: 2002 Ford Windstar mileage: 104,389.  The oil gauge on the dashboard always indicates that I need oil. When I check the oil level, it is always fine.  In addition, the temperature gauge stopped working.  As you know both of these indicators are very important, so what could the problem be?

Answer: The oil gauge is for pressure not for oil level and a low ready is normal when the engine is at normal operating temperature and it is idling.  The temperature sensor may need replacing to get the temperature gauge to work properly.

Question: 2001 Chevrolet 1500 truck mileage: 55,341.  Hello--my question is as follows: recently my oil pressure AND temperature gauge have been registering very low readings--normally the gauge indicator would register directly in the center for both oil and temperature.  The oil pressure starts out normal, but after the engine is warm, the gauge reading gets very low.  The temperature gauge really never goes up too much.  I use Mobil 5W synthetic oil and also Slick 50, I change my oil every 2500 miles.  The dipstick is showing proper oil amounts-and there are really no other recognizable problems.  Can you offer any possible suggestions for the low oil and temp gauge readings?  As a single woman, I would like to be prepared and have some knowledge before I head to a garage if necessary.  Thank you very much for your time and help.  Chris

Answer:   If only one gauge is acting up, we would say you are having problems with a sending unit.  However, because two gauges are giving you trouble, there is a good chance that the instrument cluster has a shorted circuit.

Question: 2002 Nissan Altima mileage: 40,000.  My fuel gauge and my temperature gauge no longer work.  In addition, my driver’s side door lock often freezes.   I know this is vague but if you have any ideas please help.

Answer:  The problem with your gauges may be a faulty voltage limiter.   The problem with your door locks may be a faulty door lock actuator.

Answer:   All the gauges are controlled by the computer.   Scan it for fault codes.  The information should pinpoint the malfunctioning component.

Question: 2001 Toyota Avalon mileage: 30,000.  My car has a digital instrument cluster (speedometer, odometer, fuel indicator, etc.).  The problem is that it only works when it wants to.  It will come on and go black, intermittently.  When it is on, it tends to flicker.  Is this some type of loose connection or does the entire unit have to be replaced?

Answer:   Yes, the entire instrument cluster unit should be replaced.

Question: 2004 Ford F-250 mileage: 94,000.  My digital dashboard is out.  For the last year, it would go off and on every few months.  Now it is off it seems for good how do I check for loose connection or replacement?

Answer:   From what you describe, your dash gauge cluster has failed and must be replaced.

Question: 2002 Ford Taurus, miles: 67,300. The display on the dash (all the information like the speed, how high the engine is revving, etc) is a digital and the lights are so dim that it is incredibly hard to read any information from the dash, especially the speed, at night.  How do you brighten the lights on the dash?

Answer:  Replace the dash lights behind the liquid crystal display.

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Repair Topics / Gauges