Sensors staying active switch off
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Teching In
Joined: Jan 2016
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Sensors staying active switch off Been chasing a parasitic draw (700 Ma) sensors pcm was staying hot switch off. Having done all the wiring myself (4.8 0411 with truck harness) of course I thought I had constant power on a switched hot at the PCM.... Nope. If battery was disconnected the draw dropped on re-connect to 9Ma (stereo memory) so I started thinking the PCM was bad internally somehow. Not likely but I was out of ideas. My friend says let me check something.... Connected the voltmeter up to test parasitic draw again. Switch on then off 700Ma ok no change. He then goes way low tech and smacks the column (percussive maintenance) no change. Then wiggles the key back and fourth and shazaam problem found. Feeling stupid but happy he found the problem. 
Shared this because if you have this problem it keeps the sensors on all the time ate two MAF's and was prolly gonna kill some others especially the IAC cause it's a stepper motor so just sucking power through the coils and was responsible for half the draw. This was on a 1998 Sonoma but could happen on any vehicle with a similar switch. To be clear it was the black box switch below the key switch with several heavy gauge wires.
Shared this because if you have this problem it keeps the sensors on all the time ate two MAF's and was prolly gonna kill some others especially the IAC cause it's a stepper motor so just sucking power through the coils and was responsible for half the draw. This was on a 1998 Sonoma but could happen on any vehicle with a similar switch. To be clear it was the black box switch below the key switch with several heavy gauge wires. Last edited by Trentec; Jul 17, 2016 at 04:39 PM.
