Mysterious IOD current drain
#1
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Year: 1998
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Mysterious IOD current drain
Went to start my 98 Cherokee last week, and found the battery was totally dead. The battery and alternator are both less than a year old. I charged up the battery, then I started tracing the problem at the power distribution box, pulling one fuse at a time, with an ammeter in series between the negative battery cable and the negative battery post. There was a continuous drain of 2.8 amps with the key off. I found that pulling the IOD fuse stopped all current drain.
I checked the wiring harness between the PDC and interior fuse box, but it is in good condition with no visible problem, and no effect on the current drain when moved so as not to touch the inner fender. Next I checked the inside fuse box, pulling every fuse, circuit breaker and relay one at a time. Fuse #9 stops the current flow when pulled. Moving further downstream, I pulled the connector which feeds the wiring harness running along the inside of the passenger side door sill. Pulling this connector stopped the current drain. When I reconnected this plug to the fuse box, the current drain was gone. I started the engine, and everything is working 100% correctly. Gauges fine, no check engine or airbag or check gauges lights on. No error codes from the OBD terminal. I have driven it for the last two days with zero problem. I am concerned that the problem could come back. My key will not come out in the ACC position, so that is not the problem. The fuse #9 circuit feeds courtesy lights, vanity lights in visors, portions of the instrument panel, and dome and cargo lights. Any suggestions as to what might have caused the problem, and anything.that might need to be replaced to prevent the problem in the future?
I checked the wiring harness between the PDC and interior fuse box, but it is in good condition with no visible problem, and no effect on the current drain when moved so as not to touch the inner fender. Next I checked the inside fuse box, pulling every fuse, circuit breaker and relay one at a time. Fuse #9 stops the current flow when pulled. Moving further downstream, I pulled the connector which feeds the wiring harness running along the inside of the passenger side door sill. Pulling this connector stopped the current drain. When I reconnected this plug to the fuse box, the current drain was gone. I started the engine, and everything is working 100% correctly. Gauges fine, no check engine or airbag or check gauges lights on. No error codes from the OBD terminal. I have driven it for the last two days with zero problem. I am concerned that the problem could come back. My key will not come out in the ACC position, so that is not the problem. The fuse #9 circuit feeds courtesy lights, vanity lights in visors, portions of the instrument panel, and dome and cargo lights. Any suggestions as to what might have caused the problem, and anything.that might need to be replaced to prevent the problem in the future?
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I removed the bulbs for both my glove-box and under-hood. Not worth it for me to risk finding my battery hammered over that, and something I won't see if it's the switch. Actually I removed them all since I often leave my doors open.
I suppose you could check say, the glove compartment bulb and see if it happens to be 2.8 Amps
I suppose you could check say, the glove compartment bulb and see if it happens to be 2.8 Amps
Last edited by DFlintstone; 12-17-2016 at 04:02 PM.
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I removed the bulbs for both my glove-box and under-hood. Not worth it for me to risk finding my battery hammered over that, and something I won't see if it's the switch. Actually I removed them all since I often leave my doors open.
I suppose you could check say, the glove compartment bulb and see if it happens to be 2.8 Amps
I suppose you could check say, the glove compartment bulb and see if it happens to be 2.8 Amps
i need one light, by the ignition at night!!
there was a recent thread about the #9 fuse??
2.8 a seems high for one small bulb, we do need to get some readings on that.
Last edited by nujeepguy; 12-17-2016 at 04:39 PM.
#4
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Went to start my 98 Cherokee last week, and found the battery was totally dead. The battery and alternator are both less than a year old. I charged up the battery, then I started tracing the problem at the power distribution box, pulling one fuse at a time, with an ammeter in series between the negative battery cable and the negative battery post. There was a continuous drain of 2.8 amps with the key off. I found that pulling the IOD fuse stopped all current drain.
I checked the wiring harness between the PDC and interior fuse box, but it is in good condition with no visible problem, and no effect on the current drain when moved so as not to touch the inner fender. Next I checked the inside fuse box, pulling every fuse, circuit breaker and relay one at a time. Fuse #9 stops the current flow when pulled. Moving further downstream, I pulled the connector which feeds the wiring harness running along the inside of the passenger side door sill. Pulling this connector stopped the current drain.
Look at the JB layout pic below. Can you tell us which connector it was that you disconnected.
When I reconnected this plug to the fuse box, the current drain was gone. I started the engine, and everything is working 100% correctly. Gauges fine, no check engine or airbag or check gauges lights on. No error codes from the OBD terminal. I have driven it for the last two days with zero problem. I am concerned that the problem could come back. My key will not come out in the ACC position, so that is not the problem. The fuse #9 circuit feeds courtesy lights, vanity lights in visors, portions of the instrument panel, and dome and cargo lights.
All the circuits you describe are from the IOD fuse (#16) in the PDC. #9 in the JB is for the compass, instrument cluster and the headlamp delay.
Any suggestions as to what might have caused the problem, and anything.that might need to be replaced to prevent the problem in the future?
I checked the wiring harness between the PDC and interior fuse box, but it is in good condition with no visible problem, and no effect on the current drain when moved so as not to touch the inner fender. Next I checked the inside fuse box, pulling every fuse, circuit breaker and relay one at a time. Fuse #9 stops the current flow when pulled. Moving further downstream, I pulled the connector which feeds the wiring harness running along the inside of the passenger side door sill. Pulling this connector stopped the current drain.
Look at the JB layout pic below. Can you tell us which connector it was that you disconnected.
When I reconnected this plug to the fuse box, the current drain was gone. I started the engine, and everything is working 100% correctly. Gauges fine, no check engine or airbag or check gauges lights on. No error codes from the OBD terminal. I have driven it for the last two days with zero problem. I am concerned that the problem could come back. My key will not come out in the ACC position, so that is not the problem. The fuse #9 circuit feeds courtesy lights, vanity lights in visors, portions of the instrument panel, and dome and cargo lights.
All the circuits you describe are from the IOD fuse (#16) in the PDC. #9 in the JB is for the compass, instrument cluster and the headlamp delay.
Any suggestions as to what might have caused the problem, and anything.that might need to be replaced to prevent the problem in the future?
JB:
.
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here's the pin out of C7 connector, showing which circuits go thru it.
I would be curious about that cargo bay lamp switch, pin cav 7. Thatcargo bay lamp switch has a bad habit of burning up.
.
I would be curious about that cargo bay lamp switch, pin cav 7. Thatcargo bay lamp switch has a bad habit of burning up.
.
Last edited by CCKen; 12-18-2016 at 01:31 PM.
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#9
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Thanks for that pinout CCken. I think that the cargo light circuit also is fed from the IOD fuse in the PDC. The cargo light circuit seems to be the common link between the C7 connector and the IOD drain. Is it just the switch for the cargo door that I should replace? Additionally, I did check the wiring harnesses that enter the top of the cargo door and they look fine from the outside.
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Thanks for that pinout CCken. I think that the cargo light circuit also is fed from the IOD fuse in the PDC. The cargo light circuit seems to be the common link between the C7 connector and the IOD drain. Is it just the switch for the cargo door that I should replace? Additionally, I did check the wiring harnesses that enter the top of the cargo door and they look fine from the outside.
It's the switch for the cargo bay lamp. Pull the cover down and access the switch to see if the wiring is burned up/shorted. Remove the connector and see if the IOD is still there.