Location of ground wires?

speedyg

Registered User
Location of ground wires?(problem solved)

I have been chasing a few electrical problems since my stereo install. The DIS module was replaced, because when the car would get warm the tach would die and check engine light would come on. The new DIS fixed that problem which I am sure it is unrelated to my new problem.

Now the lights will dim when rolling up the windows, and the stereo will cut out. Replaced the alt. because it tested bad. The next day the battery tested bad, so I got a brand new one under warranty. Well the tach is now acting jittery,and bounces around with the window button (no check engine light) and the same problems with the head lights dimming when I touch the windows.

So I take it back today and they say the battery is not fully charged so they recharge it and test the Alt. and it tests OK. So now my question is would the lack of ground wires be causing this problem? I only see two, one to the passanger motor mount and two, the actual ground cable from the battery to the frame front and to the driver motor mount. Is there a third? where is it? Any thoughts? thanks

I rebuilt the motor myself and could have forgotten a ground wire, these are my thoughts.

*EDIT*

It ended up being a loose connection at the round relay box mounted to the driver fender well near the battery. I tightened that up, and it fixed all the problems.

Thanks to Duffy and everyone who helped!!!!!!!!
 
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I believe there is a ground wire off one of the rear portions of the cylinder heads. As far as your problem.....when you mounted the new DIS how did you do it? Your battery charge state to me indicates you have a short in the electrical system the location being highly suspect to the Power Window or related circuits.

You can try and isolate the problem by measuring the battery drain with all normal "stuff" off. I you have greater than 1 amp (with the underhood lamp and KAM power drain) sequencially pull the fuses one at a time until you hopefully isolate the short to a circuit. Then start looking for the location.
 
Thanks Duffy, I believe I dont have that ground wire that you speak of. Which cylinder head is it on? Any pictures anyone?

I mounted the DIS by unhooking the battery, unplugging the old one and removing. I cleaned the bracket off. Then I used a razor thin layer of heat sink on the new one, bolted it on making sure to have the ground bolt tight ( right front). Then plugging it back in and hooking up the battery.

The parts guys also suggested a short. But it seems my lights pulsate even with the lopey cam at idle, or turning the steering wheel, or tapping the brakes, or cranking the volume on the stereo, or.....ect.

I really dont understand how to check this:
You can try and isolate the problem by measuring the battery drain with all normal "stuff" off. I you have greater than 1 amp (with the underhood lamp and KAM power drain) sequencially pull the fuses one at a time until you hopefully isolate the short to a circuit. Then start looking for the location.

Do I use a volt-meter hooked from the neg wire to a known ground? Sorry I really dont have much electrical background. And I would like to do this test and report back. Thanks for any input.
 
There are actually two ground "bolts" for the DIS Module so you need to check that all four of them are tight since I don't remember off hand which two are the ground ones.

To measure battery drain you need to set your voltmeter to read current or amps. Then hook it in series with the positive battery lead to read the current draw. So you would unhook the positive battery cable....hook one test lead to the positive battery post and the other to the positive battery cable you just removed. With every accessory off in the car measure the value and report back.
 
It reads .066 with the ignition in the off position. Although it started at about .087 it the fell and held steady at .066

I will respond after work this evening to anyone with ideas.

Thanks!
 
With all accessories still OFF...move the Ignition Switch to the ACC position and reread the current draw.
 
I checked the current draw with the key in the ACC position. It reads about 6.50 the only thing that seems to be on is the underhood light, from the hood being open. It did start out about 17.00 but slowly went around 6.50 and bobbled around there until I unhhoked it.
Thanks for your help Duffy!
 
There are only 4 circuits in the car energized with the ignition switch in the ACC position. Those circuits are through the following fuses.

ACC
Radio
P/W
Wiper

You can eliminate each circuit individually by pulling the fuses one at a time and then seeing on which the currect draw lowers towards your original value. Once you find the circuit that causes the mose power draw report back and we can discuss it further.

Where did you pull in power for the radio from?
 
I will check those fuses Sunday afternoon. You are refering to the under the dash fuses, right?

Is that draw too much with the key in the ACC position? Is this where the problem is surfacing from? Because after reading up on the people here with bad aftermarket alternators, I feel this may be the problem. My alt. was installed two weeks ago, and the battery swapped two days after that. Although the car always starts.

I want to contine trouble shooting. And I appreciate your help Duffy. This reminds me of your old website forums! Great technical info!

My radio is just plugged into the factory wiring,( a shop installed it, Nov. 02 ) and the amp is run from the battery, to the trunk with 8 gauge wire (by me, Aug 03).

Thanks again
 
...

get your multimeter and set it to continuity, then touch both leads together (should hear a beep, test to make sure you have it on the right setting) then put 1 lead on your positive battery terminal, then put the other lead on your negative battery terminal while the car is off, it should not beep, if it beeps you have a short somewhere, then start your car and do the same, still shouldnt beep...
What does your battery read for voltage with the car off ?
(does the voltage drop fast, it should drop but not that fast ??)
What does your battery read for voltage when the car is on ?
now put the a/c + stereo + high beam lights on, then what does the voltage read ?

Alex LaChance
 
Problem solved

It ended up being a loose connection at the round relay box mounted to the driver fender well near the battery. I tightened that up, and it fixed all the problems.

Thanks to Duffy and everyone who helped!!
 
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