ckp and cmp sensor test

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Jun 28, 2010 | 02:03 PM

raptor2005

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ckp and cmp sensor test

hey everyone i was wondering if any knows how to test the ckp and the cmp sensor. i was told this can be my problem for a no start and was wondering how to test them. if any one can help thanks.

Jun 28, 2010 | 02:43 PM

m-chan68

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From: Woodbridge, Ontario, CA

Quote:

Originally Posted by raptor2005

hey everyone i was wondering if any knows how to test the ckp and the cmp sensor. i was told this can be my problem for a no start and was wondering how to test them. if any one can help thanks.

The spec is between 300 to 400Ω for the CKP sensor, and 800 to 1100Ω for the CMP sensor. If you want to check readings, set your DVOM to read Hz. The CKP reading you should be getting from the CKP sensor, is between 150 to 200Hz, directly proportional to engine cranking RPM when the engine is cranked over. The CMP reading should be between 1.1 to 1.9Hz when the engine is cranked over.

Jun 28, 2010 | 07:20 PM

cheezit

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From: N. Fort Worth, tx

any chance you have a lab scope thats 2 channel? if so I tell you the better way. if not m-chans will get you some info.

Jan 20, 2013 | 01:59 PM

jhedic

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I have a question pertaining to this.... with the ckp unplugged I get 3.05volts from one pin in the connector and 3.07 on the other. Should I have voltage to both sides? I thought only one side should be powered as the other is a return voltage as I understand it. Can anyone please help

Jan 20, 2013 | 02:10 PM

cheezit

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From: N. Fort Worth, tx

you should not have voltage at all. it produces its own ac signal from magnetic induction.
you should be disconnected from the pcm and the ckp and check for short to power,short to ground, short to the other pin
from there load testing the circuit

Jan 20, 2013 | 02:52 PM

jhedic

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Thanks cheezit. I am a little red in the face but I was looking at the cmp not the ckp. So I still have 1.25 volts at both connector pins on the ckp and 370 ohms on the ckp itself? Should the resistance change if the magnet is in contact with a metal surface or always stay the same?

Jan 20, 2013 | 03:30 PM

cheezit

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From: N. Fort Worth, tx

so with the ckp unpluged at both ends you have voltage? should not be any.
if you search for cmp or ckp vaules m-chan has them some were. i never really check my that way