Grand Cherokee/ parasitic drain

Vehicle has been in the shop several times within one month( Battery test, replace accelerate idle switch, rear end replace)
latest delema is with a constant clicking sound coming from under/ near dashboard on passenger side . No interior lights. All this occurs before I turn over the ignition. On some occasions if I enter the vehicle and don’t hear the constant clicking sound. Whola, the vehicle starts every time. I disconnect the battery cable when coming in over night. Any suggestions, comments on possible parasite drain would be useful. 1997 112,ooo miles.

A blend door would be my guess, Here is some helpful info if you want to pursue it.

Good idea above, definitely check that. Also any good auto-electric mechanic could check which circuit is causing the parasitic drain. They just measure the total drain at the battery then remove the fuses one by one the battery drain stops. Generally once you know which circuit it is, you can find the device that is causing it fairly quickly by unplugging connectors.

@Barkydog, I just returned from trying to start the jeep. The battery had been disconnected for a few days. well once I made the connections, it didn’t start or make the the constant clicking sound. I will invest in an Ammeter and perform the test before I have it towed back to the repair shop. As well as check the door jams, fuses, glove compartment light, and possible other culprits. Thank you for the popluar mechanics information.

Car been in shop all week . shop owner says it started everyday. he was only able to detect a drain of 5/25 very small drain. says battery is 4 years it may need replacing.

When you connected the battery did the starter at least work when you tried to start it? If the starter didn’t work then you may have a bad connection to power at the battery connections or the wiring going to and including the ignition switch.

If the battery goes dead in a short time while it isn’t connected it should be replaced.

Did you ask the shop to identify what is making the contant clicking sound?

@ Cougar, no, the car would not start the dash lights didn’t even come on. @ Nevada, Yes, I did ask the mechanic. about the clicking sound, He gave me a round about answer that didn’t make sense. Well as of this date, I’m seriously considering parting out my faithful dependable black beauty… the car was in the shop 5 day this past week, The mechanic said that it started up everyday. Well 1 day after I get it home, it doesn’t start… No clicking sound to warn me that it wouldn’t start, It just didn’t turn over. Yes the dash lights came on but that was far as it went. I really believe that the mechanic knows how to work on some things, But My gut really tells me that he was not able to perform an extensive electrical testing on every probably drainage… Is there a such thing as shop that can test only electrical?

You are describing what could be a simple bad connection somewhere between the battery and the ignition switch. There are usually two wires that come from the positive battery post, though sometimes the second wire can be tied to the starter solenoid where the first, or main connection ties too. The smaller second wire from the battery is what we are concerned with. That wire ties to the electrical panel under the hood, which supplies power to all the accessories of the car. There should be a main fuse inside the panel. You could check to see if power is getting to that fuse when the trouble happens by using a cheap test light probe. If that is okay then should check to see if power is getting to the ignition switch. There is a reasonable chance the switch connection has a problem. This is a simple problem to find and fix while the trouble is occurring. If you could at least prove power was getting to the main panel while the fault was there it would really help pin the problem area down some.

You stated that the dash lights worked the last time the trouble happened so it is possible that there is a problem with ignition safety switch connection to the starter solenoid. This is a common problem also. Power from the ignition switch passes through a safety switch that is activated when the shifter is in the Park position. If that switch fails then no power gets to the starter solenoid which switches power to activate the starter motor via the first, or main battery cable I mentioned earlier.

There are places that specialize in electrical repairs and would have no trouble fixing this if they can get it to fail while they have it. If you would like to keep the car for some time longer I wouldn’t give up on it, though I know it is very frustrating to have a car you can’t always depend on.

A four year old battery could indeed need replacement. Batteries rarely last more than 5 years, and a 4 years demise isn’t uncommon, especially in hot climates. If the mechanic kept the car inside, and you keep it outside, that could also explain why it started for the mechanic and not for you, as available battery power goes down with temperature. Has the battery been load tested yet? That’s the way to tell one way or another. What does the mechanic mean by a drain of “5/25”? I’ve never heard that terminology before. Usually everything-off-condition battery drain is 50 mA or less. What is the measured parasitic drain in units of mA?


Any mechanic with brains in his head and a decent multimeter can perform a parasitic draw test

However, if the brains and/or the decent multimeter are missing, forget it

@Patty, some mechanics lack the patience/interest to trace troublesome battery drains. You may have to find another mechanic or do it yourself.

In their defense, these intermittent electrical problems can be a real pain to track down. Sometimes you have to bite the bullet and do it yourself.

@Jesmed, I believe this is my situation.