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I have been around electrical and electronic stuff all my life all that way back to repairing tube style radios and TVs in the 60's, and I thought I knew how to interpret DVM test results under a car hood. :laugh2: yep, Good one!
I was about to chop off a female two wire connector on my daughters Saturn...when I got an on line hint from the SaturnFans site guys.
I had tested the electric solenoid, with a 9 volt battery, and it worked. I had tested the female connector and it had 14 volts (reading volts across the top of the two exposed metal contacts on the end of the female push on connector, one of those new ultra tiny do-jobbers from GM/Saturn), so I decided the inside of the female connection must be bad on one side. Tried adjusting it with a tiny jewelers screwdriver, NO JOY.:rattle:
Then this guy tells me the meter (High impedance DVM) may be lying to me (Yah, right) , tells me one wire is always hot, the other is grounded through the PCM by a solid state switch, that may leak enough to make my meter show a complete circuit, that is not complete and functional.
So I check, and sure enough the ground leg shows 500,000 ohms to ground, when it should be about 1-2 ohms. Now my real problem is the wiring to the PCM or the electronic solid state ground switch that is in the PCM.:tears:
IIRC our fuel injectors are grounded to fire them via the ECU/PCM on our jeeps. So moral of this story, is that one needs to check and see if the ground is actually firing, actually a solid ground, or just a poor ground that fools the high impedance DVMs. Testing the contacts at the end of the wiring harness connection may not be telling us the entire story folks!
I was about to chop off a female two wire connector on my daughters Saturn...when I got an on line hint from the SaturnFans site guys.
I had tested the electric solenoid, with a 9 volt battery, and it worked. I had tested the female connector and it had 14 volts (reading volts across the top of the two exposed metal contacts on the end of the female push on connector, one of those new ultra tiny do-jobbers from GM/Saturn), so I decided the inside of the female connection must be bad on one side. Tried adjusting it with a tiny jewelers screwdriver, NO JOY.:rattle:
Then this guy tells me the meter (High impedance DVM) may be lying to me (Yah, right) , tells me one wire is always hot, the other is grounded through the PCM by a solid state switch, that may leak enough to make my meter show a complete circuit, that is not complete and functional.
So I check, and sure enough the ground leg shows 500,000 ohms to ground, when it should be about 1-2 ohms. Now my real problem is the wiring to the PCM or the electronic solid state ground switch that is in the PCM.:tears:
IIRC our fuel injectors are grounded to fire them via the ECU/PCM on our jeeps. So moral of this story, is that one needs to check and see if the ground is actually firing, actually a solid ground, or just a poor ground that fools the high impedance DVMs. Testing the contacts at the end of the wiring harness connection may not be telling us the entire story folks!