Mechanics

INSTALL SOLENOID TO DISCONNECT BATTERY

1989 Isuzu Trooper

Electrical problem
1989 Isuzu Trooper 4 cyl Four Wheel Drive Manual 145000 miles

I have a slow batter drain in my hunting and farm SUV electrical system that I have been unable to locate. I am installing a Ford starter solenoid in the battery ground cable to disconnect the battery when I turn off the ignition switch.

Please tell me on which or both of the two smaller solenoid terminals I need to connect the ignition switch wire.

Does it make any difference which of the two battery cable terminals I connect the battery ground wire, block to solenoid and solenoid to battery terminal?
Avatar
Al Barrs
January 3, 2009.



If you put the solenoid in. Then the ignition switch isn't going to have any power to energize the solenoid.

You will have to run independent wires from the battery to a toggle switch and then to the solenoid.
And the solenoid will still have to be grounded to the battery.

But to answer your question, you would put the exciter wire on to the post next to the letter " S"

Buddycraigg
Jan 3, 2009.
Buddy; I am sending a diagram I drew for wiring the battery disconnect circuit. Is this what you suggested and Is it what I need? THANKS!

Let me know if you didn't get the diagram. I can't see if it uploaded or not. Thanks

Al
Retired
albarrs@wfeca. Net

Tiny
Al Barrs
Jan 4, 2009.
Try sending the diagram to my email address.

but be sure to copy this link in the message
http://www.2carpros.com/forum/viewtopic.php?p=444157

to help me find what we are talking about.

Buddycraigg
Jan 4, 2009.
What is your e-mail address Buddy?

My e-mail is albarrs@wfeca. Net

Thanks,
Al

Tiny
Al Barrs
Jan 4, 2009.
Sent via email

Buddycraigg
Jan 4, 2009.
I applaud your efforts but the way you have it.
the two grounds i have circled will not be grounded.


http://myfiero.com/uploads/15099_.jpg


.
.
i'll be right back.
.
.
try this.
and be sure the solenoid you get is rated for "constant duty"
and keep in mind, if you have any problems with the contacts in the solenoid, everything in the system will try to ground through that little switch


http://myfiero.com/uploads/15100_.jpg


Buddycraigg
Jan 4, 2009.
I guess you are against the idea of using something a little low tech.
like


http://toolmonger.com/wp-content/uploads/2008/07/BatterySwitch-450.jpg



or


http://www.outbackers.com/forums/uploads/1154134718/med_gallery_2363_3_32210.jpg


Buddycraigg
Jan 4, 2009.
Thanks for the reply Buddy! You are the greatest help I have found on the Internet.

I ordered one of the battery disconnect switches like you posted, but was concerned that I couldn't run a heavy battery cable into and back out of the cab to the battery and if I couldn't do that and installed the switch under the hood I would still have to remember to raise the hood each time I stopped to turn off the battery disconnect switch. The length of battery cable stopped me from this idea that even I had though of as a first and easy fix.

Thanks for the revised wiring diagram I sent you!

But, I now have a different problem and have decided the best move for now is to put everything back to original and keep raising the hood and removing the negative battery cable to prevent the slow battery drain from killing my new battery. I need to use the vehicle for a couple more months and it will mostly sit over the summer until later this year. Here is what is going on now.I'll start from the beginning.

The problem started with a slow battery drain that would run even a new battery down to zero over several days sitting time.

First as you suggested then, I removed the negative battery cable from the battery. Using a 12-volt test light, I hooked one end to the negative battery post and hooked the other end to the negative battery cable I had disconnected.

You said that the test light will glow or “light” if there is an electrical drain. You said, if the “light or glow” is faint, that is probably normal draw for the clock or computer, I was told. And I was told, if the “light or glow” is bright, then there is a large electric current drain. That circuit could then be troubleshot and corrected or isolated to stop the battery drain.

I then removed and replaced the fuses one by one looking for the test light glow to go out knowing that the one that distinguished the bright light would be the circuit with the battery electric drain.

Unfortunately, the test light never went out.

Second, I tried to install a Ford solenoid in the negative battery cable circuit from the negative side of the battery to the engine block ground bolt. I then tested the solenoid with a temporary wire from the positive terminal of the battery to the ‘S’ terminal on the Ford solenoid, nothing happened. I then tried touching the ‘I’ terminal on the Ford solenoid, nothing happened. I then attached a short wire from the ‘S’ terminal on the Ford solenoid to the vehicle frame and tried again. This time a touch to the ‘S’ Ford solenoid excited and activated the solenoid and I thought I was home free.

To make sure I hadn’t blown a fuse, fuseable link or something I put the wiring configuration back (original) as it had been before I installed the Ford solenoid in the negative ground battery cable and got in the vehicle and started the engine. It ran fine.

At this point I believed that all I needed to do was figure out how to connect a circuit from inside the vehicle from the dash to the Ford solenoid to excite the solenoid and energize the starter system so I could then turn the ignition key to start the engine.

I drove my wife's car to town to buy a toggle switch and a roll of wire to make the connections. When I got back I had a call about something that required me to use the Trooper to pull a small trailer so I first checked that everything under the hood was back in it’s original place and disconnected the Ford Solenoid and the extra wiring I had done earlier.

I connected the original Isuzu negative battery cable and got into the cab and inserted the ignition key. When I turned the ignition key all the dash lights and instruments activated normally, but when I tuned the key to the start position absolutely nothing happened. There was no starter Isuzu solenoid click, no starter grind and no dim lights…nothing. All was quite!This made me believe I had somehow blown a fuse, perhaps the ignition fuse. I check the fuses and could not find any that had burned out. Now I am at a loss as to what went wrong or what to do.

I have the wiring back to the original Isuzu configuration with the Ford solenoid and its wiring disconnected and isolated so there is no influence on the original Isuzu starter wiring circuit configuration.

WHAT MIGHT HAVE HAPPENED THAT THE IGNITION SWITCH DOESN’T EXCITE THE ISUZU STARTER SOLENOID NOW?

I tried to get to the starter to directly excite the starter solenoid to see if it was working but haven’t been able to get my vision or hands to it because of the closeness. I suppose the vehicle has to be on a lift to get to the starter… FRUSTRATED!

Can you suggest what might have happened to the original Isuzu starter circuit to render it inoperable now?

Forget about the Ford solenoid for now! I just need to get her back running for a couple of months and can then figure out how to either locate the battery drain circuit or install the controller Ford solenoid…

Thanks very much for all your help,
Al Barrs, Retired
albarrs@wfeca. Net

Tiny
Al Barrs
Jan 6, 2009.
Buddy; See e-mail for wiring diagram> > > I checked for continuity with my ohm meter and determined that there was continuity between location A and Location B in the following wiring diagram you modified. A and B are marked in GREEN. I am of the opinion that this would direct positive current to the ground on the Trooper's frame. Am I wrong?

See e-mail for wiring diagram> > > Thanks,
Al Barrs
albarrs@wfeca. Net

Tiny
Al Barrs
Jan 6, 2009.
Yes, A and B would have continuity because of the coil windings of the solenoid.

But when the solenoid is at rest, the frame is not grounded. Because it's not connected to the battery.

That is why I added the black wire and used a double pole switch.

Buddycraigg
Jan 6, 2009.
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