OldSch88L Posted May 13, 2020 Share Posted May 13, 2020 Hey guys, I have a slight parasitic draw on my 1988 Comanche 2.5L 5-speed. Did a little testing, and the only amp draw change I get is when I pull out the ETR fuse, which I guess it's normal since it runs the clock and radio memory, and the major one is the TRANS fuse, which stays pretty warm even though the ignition is off. That fuse seem to control only the backup lamps circuit in the case of a 5-speed, and should be hot only in ACC or RUN, via the ignition switch according to the diagram. So my question is: what would you advise next? Go test the ignition switch and wiring in the steering column? I always disconnect my negative terminal when I park it for the night, but when I connect it back on, the big metal relay next to the battery clicks on; is that normal? Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 13, 2020 Share Posted May 13, 2020 Quick question. Does the truck shut off normally when you remove the key? Link to comment Share on other sites More sharing options...
OldSch88L Posted May 13, 2020 Author Share Posted May 13, 2020 Yes, truck starts and shuts off fine, but if I leave the battery connected, it's getting pretty weak at the end oof the week Link to comment Share on other sites More sharing options...
Ωhm Posted May 14, 2020 Share Posted May 14, 2020 Are backup lamps ON all the time? Link to comment Share on other sites More sharing options...
OldSch88L Posted May 14, 2020 Author Share Posted May 14, 2020 22 minutes ago, Ωhm said: Are backup lamps ON all the time? Nope just came back from checking, and they work like they should Link to comment Share on other sites More sharing options...
Ωhm Posted May 14, 2020 Share Posted May 14, 2020 2 hours ago, OldSch88L said: So my question is: what would you advise next? Remove the fusible links and see if you can determine which one has current draw on it. Link to comment Share on other sites More sharing options...
OldManComanche Posted May 14, 2020 Share Posted May 14, 2020 I had a problem like this. The wiring had been badly hacked up. I spent several days straightening out the wiring trying to find the problem, but no success. I was sitting in the truck wondering what to do when I noticed the cigarette lighter was pushed in. I pulled it out and noticed the end of it was warm to the touch and all crudded up. I left it out for a couple of days and the current drain went away. I guess that it acted like a big resistor and slowly drained the battery. Good Luck Link to comment Share on other sites More sharing options...
OldSch88L Posted May 16, 2020 Author Share Posted May 16, 2020 Gave it another go today; seems I did it wrong the first time The real culprit is in the startiing circuit, the starter relay always stay energized for some reason, Even with the ignition switch unplugged, I still get a 0.34 amp, 0.5 volt draw. As soon as I unplug the small pinkish-red wire from the relay, the multimeter drops to zero. So my question is: does the relay normally activate with constant power and grounding it, or the opposite, constantly grounded and activating when receiving power from the positive terminal? Link to comment Share on other sites More sharing options...
Ωhm Posted May 16, 2020 Share Posted May 16, 2020 55 minutes ago, OldSch88L said: I still get a 0.34 amp, 0.5 volt draw. As soon as I unplug the small pinkish-red wire from the relay, the multimeter drops to zero. 88 Electrical Manual shows three (3) single connectors for the Starter Relay. C331 DK GRN (SOL) C332 BLK w/TR (G) C333 GRN (I) Link to comment Share on other sites More sharing options...
OldSch88L Posted May 16, 2020 Author Share Posted May 16, 2020 1 minute ago, Ωhm said: 88 Electrical Manual shows three (3) single connectors for the Starter Relay. C331 DK GRN (SOL) C332 BLK w/TR (G) C333 GRN (I) I got the black with white tracer, and pink or faded red, and I got nothing on the C331 terminal Link to comment Share on other sites More sharing options...
Ωhm Posted May 16, 2020 Share Posted May 16, 2020 I take it this vehicle STARTS and SHUTS OFF just fine, with the IGN SW. Link to comment Share on other sites More sharing options...
OldSch88L Posted May 16, 2020 Author Share Posted May 16, 2020 41 minutes ago, Ωhm said: I take it this vehicle STARTS and SHUTS OFF just fine, with the IGN SW. Yes it does! Link to comment Share on other sites More sharing options...
Ωhm Posted May 16, 2020 Share Posted May 16, 2020 I'm wondering if the Starter Relay has anything to do with STARTING the vehicle. Does vehicle START with the two (2) wires removed from the Starter Relay. The reason for question is you have no wire on the SOL terminal of the Starter Relay. Link to comment Share on other sites More sharing options...
OldSch88L Posted May 17, 2020 Author Share Posted May 17, 2020 Gonna go try, be right back, I'll also snap a couple pictures Link to comment Share on other sites More sharing options...
OldSch88L Posted May 17, 2020 Author Share Posted May 17, 2020 I think you nailed it Ohm; it starts with both wires disconnected! I poked around in the mess of wires and found this... Dark green wire spliced with electrical tape... I think we found the solenoid wire! Man, I just keep finding some hacked jobs on this truck; funny thing is both previous owners were brothers, early twenties, supposedly "mechanics" both of them... Thanks for the help kind sir, will keep you updated once I've sorted this out! Link to comment Share on other sites More sharing options...
OldManComanche Posted May 17, 2020 Share Posted May 17, 2020 On 5/13/2020 at 9:37 PM, OldManComanche said: I had a problem like this. The wiring had been badly hacked up. I spent several days straightening out the wiring trying to find the problem, but no success. I was sitting in the truck wondering what to do when I noticed the cigarette lighter was pushed in. I pulled it out and noticed the end of it was warm to the touch and all crudded up. I left it out for a couple of days and the current drain went away. I guess that it acted like a big resistor and slowly drained the battery. Good Luck I don't think the wiring was great to begin with. I have had 3 Comanches, and all 3 have had wiring repairs that were POOR! Wire ends that had the insulation cut off and the dirty bare wires twisted together, or wire splices with much smaller gauge wiring being used. No tape or insulation of any kind. CLEAN WIRE ENDS, SOLDIER, AND SRINK TUBING ARE YOUR FRIEND!! (along with patience) Link to comment Share on other sites More sharing options...
Ωhm Posted May 18, 2020 Share Posted May 18, 2020 @eaglescout526 could it be someone else has found another use for the Engine Compartment Lamp connector? Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 18, 2020 Share Posted May 18, 2020 1 hour ago, Ωhm said: @eaglescout526 could it be someone else has found another use for the Engine Compartment Lamp? LOL! That's TWO improper ways to use that plug. Oh lord. Whats funny is if his truck would've kept running while off, that plug would've been my theory. Link to comment Share on other sites More sharing options...
OldSch88L Posted May 21, 2020 Author Share Posted May 21, 2020 All fixed! So to resume, yes, that was the uunderhood lamp wire plugged on the starer relay rather than ignition switch positive. That's what was causing my draw. And then, the ignitiion positive (green) was spliced directly to the starter solenoid (dark green) so basically, all the current went through the ignition switch instead of the relay every time I started... Yikes! Restored everything to how it should be and everything works perfect, which makes me wonder why it got jerry-rigged that way in the first place. Thanks a lot everyone!!! Link to comment Share on other sites More sharing options...
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