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Discussion Starter · #1 ·
I have another thread regarding my ABS warning light. Now I have a different problem. When I tried to start the car yesterday, nothing happened when I turned the key to start. No clicking sounds, dimming lights, etc. nothing. It didn't seem like a dead battery problem since the voltage (with the engine off) was 12.6V. The charging system was working with DashCommand showing a steady 13.9-14.1V the last time I drove the car.

The same thing happened a number of years ago and I traced the problem to a bad starter relay. I switched the headlight relay for the starter relay since they both have the same part number. No change. But when I used a jumper across the relay terminals that would close to send power to the starter, the engined started up easily.

Based on the wiring diagram I have, it looks like there is a safety switch on the clutch pedal that could be the problem. The other likely problem is a bad ignition switch. How big a job is it to change the ignition switch if I'm not lucky and the problem is the clutch safety switch? Am I overlooking another possibility?

Thanks,
David
 

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More likely the starter solenoid switch contacts are worn out and need replacing.
The starter solenoid switch contacts connect the Red battery cable to the starter motor armature.
Applying +12 Vdc to the H-1 connection will energize the starter solenoid switch solenoid, which in turn closes the switch contacts.
 

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If you measure +12 Vdc at connector H-1 when the Ignition Switch is in the Crank position the Ignition Switch, Clutch Switch, Starter Solenoid Relay and wiring to H-1 are OK. If you can hear the starter solenoid click when voltage is applied to H-1 the problem is in the replaceable switch contacts or the starter motor.
 

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Discussion Starter · #5 ·
It seems I am dealing with my second broken wire issue. Several years ago I was having a problem with the engine running roughly for awhile, then the problem went away for a long time and then it would return. For several years the engine ran fine, but the check engine light was always on. I finally tracked down the problem to a broken wire between the PCM and one of the outputs on the TPS.

Now, to my current issue. It looks like there is a break between the output side of the clutch safety switch and the starter relay. The output side of the clutch safety switch has 12V with the key in the run position. This is correct by my reading of the wiring diagram. Then the wiring diagram shows a straight run to the terminal with the black/green wire on the starter relay; one of two terminals used to energize the relay coil.The other wire comes from the PCM. However, there was no voltage at the terminal with the black/green wire with the key in the run position. Similarly, there was no conductivity between that terminal and the clutch safety switch. I ran a jumper wire from the clutch safety switch to the starter relay. Hit the key and the engine started easily.
 

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Discussion Starter · #7 ·
This information would have been helpful in deciding where to splice in a new wire. I went directly from the output side of the clutch safety switch to the black/green terminal on the starter relay. The starter has engaged without hesitation with every try since installing the wire. But there is one weird thing. I did all of the wire tracing with the electrical connection disconnected from the clutch safety switch. When I reconnected the safety switch, the starter would only engage if I did NOT depress the clutch pedal. That is, the switch was working the opposite of its normal function. For now, I just jumped across the two terminals of the switch connection until I can get a new switch.
 
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