PCM low voltage

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Mar 17, 2012 | 02:41 PM

#11

Mannyman6600

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this is the used pcm that i install not the one the truck had will still have codes even tho it wasnt from this truck ?

Mar 17, 2012 | 02:45 PM

#12

Mike

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So, you take the old PCM out, put the new one in, turn power on, scan for codes and you still see the same one?

Mar 17, 2012 | 03:03 PM

#13

Mannyman6600

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yes when i check the voltage for the tps and the map they both have 1.2 volts instead of 5

Mar 17, 2012 | 03:28 PM

#14

Mike

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Conduct the same test, instead connect the negative lead of your multimeter to the PCM case.

Mar 17, 2012 | 06:18 PM

#15

Danthurs

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https://www.gmforum.com/showthread.p...68#post1390952

Mar 19, 2012 | 01:51 PM

#16

Mannyman6600

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I did the test on the neg to the PCM case and I still have the same voltage 1.2 to the sensors on both sides the PCM pin and all the way to the sensor

Mar 19, 2012 | 02:09 PM

#17

Mike

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Uh, dumb question, but where are you getting that you need 5V from that pin?

Mar 19, 2012 | 03:19 PM

#18

Mannyman6600

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I search on how to test the sensor and they said first thing it'* to check if the sensor is receiving 5 volts and good ground from the PCM I check ground it'* good and I am not receiving the 5 volts

Mar 19, 2012 | 03:34 PM

#19

Mike

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From: Dark Side, AZ

Reason I ask is, your on a 2nd pcm giving out 1.2 volts. It just made me wonder if thats what the voltage is suppose to be.

I don't remember, but you did test/replace the TPS?