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#4895 of 4968 Re: 2001 Pontiac Montana has a parasitic drain [montanaguy] by montanaguy Aug 16, 2009 (3:36 pm)
Replying to: montanaguy (Aug 16, 2009 3:11 pm) A little more info; on the starter motor assembly, where the positive battery cable connects, are three additional smaller cables. From bottom to top on the bolt they are (a) two wires with some wrap and an eye, (b) a thin wire and an eye, and (c) a thick wire with lots of wrapping and an eye. If I take them all off the bolt and touch the battery cable eye to (a), the frame of the van goes hot. Touching (b) and (c) has no effect. Touching just the bolt on the starter has no effect. So the problem is somewhere behind those two wires on (a). They disappear into harness shielding so I can't see where they go.
#4896 of 4968 Re: 2001 Pontiac Montana has a parasitic drain [montanaguy] by kiawah Aug 16, 2009 (3:39 pm)
Replying to: montanaguy (Aug 16, 2009 3:11 pm) I don't have the electrical schematic for your vehicle, but in most cars there is always a number of circuits that are powered and on all of the time. For instance, in order for your electric door opener to receive a key-fob signal and unlock the doors, it has to be continually powered on and working. That key fob also automatically turns on lights. Security systems, engine computers, gps tracking systems, clocks, etc are usually all on all of the time. I personally know of a power seat switch/motor go bad draining power, and a trunk light switch defective leaving the trunk light on all of the time. You could also have a diode in the alternator bad, allowing the battery to drain. If you are trying to trouble shoot something draining your battery, I can't imagine trying to do that without a set of electrical schematics. Once you have the schematics, you'll see a set of circuits that get turned on when the key is started, usually through a relay. Look for all of the circuits that are powered all of the time, and start unplugging their fuses until you see the current draw stop. Replies to this message: imidazol97 (Aug 17, 2009 5:22 am) kiawah (Aug 17, 2009 7:35 am) imidazol97 (Aug 17, 2009 10:17 am) and 1 more...
#4897 of 4968 Re: 2001 Pontiac Montana has a parasitic drain [montanaguy] by bolivar Aug 16, 2009 (9:22 pm)
Replying to: montanaguy (Aug 16, 2009 3:11 pm) Well, I think you are doing it wrong. You are using a voltmeter. What you need is an ampmeter. And one that can handle a significant amount of current (amps). If you have a multi-meter and are using the voltmeter on it, and it also has an ampmeter, it is probably not capabile of handling the amps in an auto circuit with a short - you may burn the multi-meter up if you use it's amp measurement setting. It will probably only be capabile of handling 0.1 amp or less. If you can obtain an ampmeter, you should first pull one of the battery cables and put the ampmeter in series with the pulled cable. (In other words, let all the current flow thru the ampmeter. This is how ampmeters work, and means you must have one that can handle 5 or 10 amps, because this may be the size of the current drain in your car.) This should show you the amount of current the short or failed component is pulling because this is measuring the entire electric circuit of the car. You should seen a relatively large drain, more than .3 amp. Reconnect the battery cable and then you should restart pulling fuses. Connect the ampmeter in series across the contacts where the fuse is plugged. The ignition should be off, doors closed, interior lights off, etc - in other words the car should be as dead as you can get it. If there is significant current draw across any fuse, this is probably the circuit with a short. Significant, means, oh, .3 amp or more. If your battery is going from fully charged to dead in one day, you will probably find a greater amperage pull than that. But if you find the fuse, all you have done is narrow it down to that circuit. You will still have to find the component that is actually causing the drain, or the area of wiring that is shorted to ground. This is where having an electrical diagram of the car is almost always necessary. And, here is my standard input to battery drains - Does the car have ANY non-stock alarm, remote start, after market stereo, towing package, or any electrical add-on. In MOST cases, if any one of these is on the car, this will, in MANY, MANY cases, be the cause of the drain!!!! You MIGHT be able to use your voltmeter to narrow down the circuit. When you pull a fuse, with the car 'dead', put the voltmeter across the fuse contacts. If you read any voltage at all, it means that circuit is pulling some current. You don't know how much, but it does mean some current is being pulled. The problem - several circuits (fuses) can correctly pull some power where the car is shut down. The radio will pull current to run the clock that is in most radios. The various computer boxes may pull power because some are always active 'looking' for something to happen, such as the remote lock fob being pushed to open the doors. In a modern car, who knows exactly which circuits are 'active' and pulling current when the car is shut down. The only thing - these circuits should not be pulling much current, or the battery would run down. That why I said to look for 1/3 amp or more if you can get an ampmeter. Also, your battery must have a pretty good charge in it. If you are testing with a dead battery, your amp/volt meter will not have enough current from a dead battery to detect a pull. Parasitic drains are not easy to diagnoise. You might have to take to a shop. If you do, specifically ask if they have anyone that understands electrical systems. Not every 'mechanic' knows enough to find a short or failed component.
#4898 of 4968 Re: 2001 Pontiac Montana has a parasitic drain [kiawah] by imidazol97 Aug 17, 2009 (5:22 am)
Replying to: kiawah (Aug 16, 2009 3:39 pm) Here's a good article about drains and parasitic drains. Your amp load between the terminal and the cable should be under 35 milliamperes (0.035 amp). http://flashoffroad.com/electrical/Batteries/BatteryDrain.html Replies to this message: kiawah (Aug 17, 2009 7:35 am) imidazol97 (Aug 17, 2009 10:17 am) kiawah (Aug 17, 2009 10:26 am)
#4899 of 4968 Re: 2001 Pontiac Montana has a parasitic drain [imidazol97] by kiawah Aug 17, 2009 (7:35 am)
Replying to: imidazol97 (Aug 17, 2009 5:22 am) good writeup .......thanks for posting. Replies to this message: imidazol97 (Aug 17, 2009 10:17 am) kiawah (Aug 17, 2009 10:26 am)
#4900 of 4968 Re: 2001 Pontiac Montana has a parasitic drain [kiawah] by imidazol97 Aug 17, 2009 (10:17 am)
Replying to: kiawah (Aug 17, 2009 7:35 am) Thanks for commenting. I actually tried to find some posts where people had been trouble shooting drains in GM cars which I've read, but I couldn't find any in other discussions. The one thing I wonder about is the starter. A neighbor had troubles that weren't there sometimes and occurred occasionally after 10 hours or so. A shade tree mechanic on the other side said it might be starter; they replaced the starter and the problem was gone. Replies to this message: kiawah (Aug 17, 2009 10:26 am)
#4901 of 4968 Re: 2001 Pontiac Montana has a parasitic drain [imidazol97] by kiawah Aug 17, 2009 (10:26 am)
Replying to: imidazol97 (Aug 17, 2009 10:17 am) It could be so many different things it's not funny. It only takes is one diode to go bad, one relay point to stick, one switch to stick closed, one of the computers to go bad, etc. That article just saves a lot of writing and explaining....so thanks!
#4902 of 4968 Starting and stalling problems by jhayes9835 Aug 17, 2009 (9:29 pm)
I have a 1996 Infinity I30. I was experiencing starting problems and stalling at stop lights. I would have to push on the accelator to get it to start. At stop lights I would have to keep one foot on the brake and one on the accelator to keep it from stalling. I bought some crc maf sensor cleaner and cleaned the maf sensor. The car is running fine now. I am sure That I will eventually have to replace the maf. If the check engine light never came on, will I still have to reprogram the ECM? Can I reprogram that myself? Thank you for your help.
#4903 of 4968 Re: Belt noise [pgilbert] by alternator Aug 19, 2009 (3:26 pm)
Replying to: pgilbert (Aug 16, 2009 2:45 pm) Here's something that has worked for me, and it's very inexpensive to try : Use "valve grinding compound" ( not "belt conditioner" ) to stop belts from squeaking Replies to this message: marsha7 (Aug 20, 2009 8:51 am) alternator (Aug 25, 2009 9:32 am)
#4904 of 4968 Re: Belt noise [alternator] by marsha7 Aug 20, 2009 (8:51 am)
Replying to: alternator (Aug 19, 2009 3:26 pm) Forgive me for asking...wouldn't valve grinding compound be too abrasive and simply eat up and wear out a belt surface??? Replies to this message: alternator (Aug 25, 2009 9:32 am)