no bus is displayed where the mileage is and i cant communicate with the compute on 2001 Dodge Ram Van 3500

Im trying to make sure that the pcm in the van is infact broken or shorted. Ive checked all the fuses and ive checked power and ground going into the pcm and that was ok but when i checked power at the connector going to the crank sensor i only had 2.7v DC when im suppose to have 5v. Do i need to go any further or is the pcm junk

by in Laconia, NH on December 31, 2013
1 answer 2 comments
ANSWER by on December 31, 2013
Got battery voltage and ground to the CKP sensor? Test the reference voltage to another sensor. Perform wiggle tests, look for signs of water intrusion at pcm harness connectors and 'rodent' damage!! You really need a flow chart for diagnosis and testing the system before condemning the pcm! Wiring harness troubles are common. Try www.alldatadiy.com
COMMENT by on January 11, 2014
thank you for answering my question. im going to recheck power and grounds over again and hope i find something wrong. there is alot of water on the wiring coming from the engine fuse block but its now frozen due to weather. i will check alldata for a flow chart, ive used it before and it has been helpful. i looks like it could take some time to find a short in the harness if thats where the problem is,thank you
COMMENT by on January 11, 2014
Sure.