Question: 1999 Honda Accord EXR mileage: 157,000. What conditions would short the voltage regulator inside the alternator and at the same time blow the headlights, interior lights, dash clock and damage the radio? The reason I ask is that after I got my car back from the body shop from collision to right front of vehicle (passenger side - battery side) they claim the electrical problems I now have were not a result of the accident since the battery tray was not damaged? Does not sound right to me. After further investigation the battery left cell was either shorted or somewhere inside there is a break thereby making it "open circuit". Would the damage to the voltage regulator have happened during the impact or during the trip home after the accident? Currently the alternator is punching out 18V. A little insight here would be appreciated.

Answer:   Electrical problems are tough to troubleshoot. Check the wiring harnesses for damage, especially the ground wires. Also, have the battery load tested to be sure there is not a shorted cell inside. 18-volts from the alternator is too high. This may be due to a missing ground wire or a faulty internal voltage regulator.

Question: 1999 Chevy Caprice mileage: 69,000. We have had a complete electrical shutdown. No dash, interior or anything. I've tried the Caprice battery in another car and it's fine. One mechanic suggested checking to see if there are fuseable links coming off the starter and see if these are shot. The Haynes manual wiring diagram shows a 60A fuse in the under hood fuse box instead of fuseable links for the '94-'96 models. Any other suggestions? I haven't crawled under the car yet.

Answer: We would start at the battery with a 12-volt test light checking for voltage on the main power leads to locate the short or bad connection.

Question: 1999 Chevy Celebrity mileage: 81,000. About 2 weeks ago, I was driving home from work at about 10 pm. Then my car CD player starts to turn on then off. It did all the way home. I thought it could be a loose connection or something. So, the next morning I checked the CD player and the amp connections everything seemed fine. I drove to work the next day everything seemed to be ok. Then when I drove home at 10 pm again and the same thing happened. It happened like that for a week. The following week I was driving home at night and my headlights started to dim, then the radio and lights both shut off, then the both came back on. Now this cycle has been repeating itself. Now my radio doesn't stay on for more then a couple of minutes then it shuts off. If you turn the headlights, the radio automatically shuts off. I noticed that when the radio and headlights shut off my seatbelt warning light comes on, and when the seatbelt light shuts off the radio and lights come back on. Also, when the radio and headlights shut off so does the dome light if it's on at the time? This cycle repeats itself the whole time I'm driving now. My uncle thinks it might be the voltage regulator, but I have no idea what is causing the problem. Do you have any suggestions?

Answer: Electrical problems are nightmares to troubleshoot. About all you can do is to check wiring for damage and or bad connections, especially the ground wires. We do not think the problem is the voltage regulator. However, it would not be a bad idea to have the battery load tested and the alternator output checked.

Question: 1999 Chevy Suburban mileage: 174,000. Last July my rear air went out, after that I started having weird problems. You could hear the blinker blink through the radio, the needle that registers charging or not would say it was not charging, the windows would roll down slow, (Electric) the blinkers would blink slow and if you locked the doors with the car on the lights on the inside would dim. My husband is not a mechanic...but he got out the book for his 97 Chevy pick up...the ignition switch was delaying to turn on too...he pulled the steering wheel off and replaced the ignition switch. The other problems seem to go away...except for one window...it will roll down a little then it is like you have to let it cool off or set then it will go a little further? Any idea of what is going on?

Answer: Good job troubleshooting your bad ignition switch. Your remaining problem sounds like a faulty power window motor or a window that is binding in the tract.

Question: 1995 Geo Metro  mileage: 80,000. What is the best source for an electrical wiring diagram for this car?

Answer: Other than the very expensive computer software and a factory shop manual, we know of no other source for a detailed wiring schematic.

Question: 1999 Dodge Intrepid mileage: 8,000.  When I start the car the gauges gas, odometer stay pegged below empty or zero. As I drive, the transmission doesn't shift out of starting gear (automatic trans.) and suddenly the car jerks a bit and the dash lights blink and the gauges start to work and the transmission shifts.  It is an intermittent problem mostly when the car is cold.  I took it to a Dodge dealer and they said it would be very costly to determine.  My husband, a mechanic, thinks it has to do with the computers not talking nicely.  Any ideas?  If it's process of elimination, where should we start?  The air bag light some times stays on if there's a connection.   I'll sell it for $4,000.  as is.    

Answer: With a voltmeter, start checking the main power wires that feed various components.  Somewhere along the line, you may lose voltage due to a bad connection.  Do the same thing with ground wires.  When you find the wire that has either a drop in voltage or no voltage you have solved your problem.

Answer: The picture you describe sounds like a comedy act but we are sure it is not funny to you.  When a conversion is done, the wiring must be integrated to the added conversion.  In doing so, something has apparently gotten loose and is shorting out.  You might want to look and see if there is a storage compartment that has a light that comes on when the door is opened.  If there is, there may be a bad switch in that compartment.  Otherwise, all we can tell you is to start checking wires and connections.

Question: 2002 Toyota truck mileage: 88,000.  When I turn on the lights the voltage drops so low that you can feel it.  It returns to normal relatively immediately.  The blinker has always turned itself off when you start turning not after the turn is completed.  When I have the blinker on you can see the voltage gauge move in unison with the blinker lights.  I helped someone start their car with jumper cables and mistakenly attached negative to positive.  Alternator tests fine.  Thanks

Answer: We would retest your alternator.  There are three diodes and it would be our bet that you “cooked” two of the three.

Question: 1998 Pontiac Grand AM mileage: 56,000: My car is in good running condition; no previous problems and now all of a sudden my lighter went out then my power locks will not open when I shut off the car or when I hit the door lock switch they won’t open or close. Now my headlights will not turn on only the high beams. I put new lamps in but no success. Any response would be greatly appreciated. Thank you

Answer: Check the fuses for a "blown" fuse.

Answer: Recheck the battery cable connectors. Also check the battery for failure.

Question: 2001 Toyota Rav4, miles: 90,880. Dear Bob and Ken, I have an electrical problem in my car. I hope you can answer it for me. A child spilled soda in my car and I believe some of it got in my tape deck. I was listening to the radio at the time of the spill but after about 20 seconds, the radio went silent and the tape deck came on. (The tape deck was installed separate from the radio.) The tape deck is still on and the car is turned off with the keys out of the ignition. There is no tape in the deck but it is trying to play. I put an old tape in and the radio played. I even tried to remove the fuse but that did not work either. I have no idea what to do next. Any advise before I have to go to the dealer and spend money that I do not have.

Answer: As a temporary fix to keep the tape deck from draining your battery, do remove the fuse to the radio and tape deck. There are probably two fuses. Remove them both. Now back to the main problem of the spilled soda. The electronics in your radio and tape deck are solid-state printed circuits. Any liquid spilled on them will short out the circuits. You can try to have them cleaned but you may find it cheaper just to replace them.

Question: 1999 Mercury Villager mileage: 63,000. I have 2 major problems at this time. I have a short somewhere in the vehicle, which mechanics cannot find. The battery and alternator were both changed and there is still something shorting out to the point that I have to disconnect the battery every night because the battery dies out otherwise. I was told to disconnect the alarm system, which I did but it is still happening. I have checked the following to see if it was drawing power: the trunk the hood, glove compartment, etc. When we connect the positive battery it sparks as if something is drawing power, though we know that the clock draws little power because it stays on. I also have a rough idle and a miss in the engine. The engine was compression checked, the fuel injectors were checked and are working well. The mechanic says that it may be the computer because they could not find the miss in the engine and/or rough idling. It feels like there is a cylinder out. The vehicle was given a complete tune up and problems still persist. Please give me your professional advice. Desperately seeking help.

Answer: Here is the procedure we use to isolate a battery drain. Remove negative battery cable from the battery. Using a 12-volt test light, hook one end to the negative battery post the other end to the negative battery cable you just disconnected. The test light will glow or "light" if there is a drain. If the "light or glow" is faint, that is probably normal draw for the clock or computer. If the "light or glow" is bright, then there is a large drain. That should be corrected. Now start removing and replacing the fuses one by one until the light goes out; that one will be the circuit with the drain. Remember to hold in the button in the door jam for the interior lights. Now about the "miss" in the engine. We would suggest doing a cylinder leak down test, also check for a "flat" cam. If the problem still exists, scan the PCM (computer) for trouble codes

Question: 2002 Chrysler New-Yorker, miles: 60,000 The factory installed alarm system is tripped. It will not reset/clear. Have tested all the contacts and sensors and even replaced the alarm module, still not working and is disabling the car. Power is pulsing and the engine is disabled through the body computer. Please help me find a repair or means to disable it. I have tried and it has at least 4 power feeds trough fuses feeding other items.

Answer: (1). Try locking and unlocking the drivers side door with the key. (The lock has a sensor in it to disarm the alarm system.) (2). You cannot bypass the alarm. It is integrated into the vehicles computer circuits.

Answer:   Your dome light can be turned on and off by twisting the knob on the headlight switch. For your defroster and seat belt light problem, check the fuse panel.

Question: 1999 Ford F150 Pickup 78,000 miles. One day everything is fine. The next morning no speed control, no horn and the air bag warning light is flashing. It flashes in series of on 3 times, off then on two times then repeats 3 then 2. I have checked fuses in distribution box and fuse panel. I would like the speed control to work and in Oklahoma, I have to have the horn to pass inspection. I got an idea I have a problem with the air bag system that is in the steering wheel and that is keeping the other things from working. If so I am SOL cause then I will have to take it to a Ford shop.

Answer: First check horn control relay (located on main fuse/power block in engine compartment. Next, check for wiring damage in or near steering column. Also, check fuseable links (big fuse) in main fuse/power block.

Question: 1998 Chrysler Fifth Avenue. The fuse for the inside lights blows, and when it doesn't, the dome light won't go out; same for door lights.

Answer: The cigarette lighter shorting out may cause the blown fuse problem. Try turning or twisting the headlight switch knob to turn on and off the interior lights.

Question: 1999 Ford Taurus, miles: 67,200, The fog lights were filled with moldy water and the bulbs were rusted along the shaft. I tried to replace one but no success. Can the fog lights work if only one has a bulb or do I need to have two new bulbs, or is there a wiring problem?

Answer:   Yes, they will work with one bulb, but it looks like you have a connection problem at the socket. Also, check for proper grounding. Disassemble to clean or replace sockets, and try to seal the fog light housing or replace them.

Question: A few days ago I went through water two feet deep and my car died in the middle of the road. I pushed it out of the water and after 20 minutes, I tried to jump-start it. After several tries, the car started. Two days later, the car stalled and the battery was dead with battery indicator sign on. I replaced the battery and the car started fine but the battery indicator light is still on. I am afraid that it will stop again, what should I do?

Answer: Have the charging system on your car checked. Your alternator/regulator may not be charging the battery.

Question: 1998 Grand Am, miles:, 78,000 I find when I turn my lights on the digital odometer and digital message board in the car goes off, they sometimes come on again but not always. As soon as I turn the lights off, they come back on.

Answer: The instrument cluster or lighting module is going bad. To fix the problem, which ever one is bad, needs to be replaced.

Question: 1995 GMC 2500 Truck. The wire harness for the tail lights was taken off and put back on, and now they don't work. One blinker works ok and the other is very dim. There are no running lights or brake lights.  Any suggestions?

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