642
UnclassifiedElectrical
What This Code Means
DST displays MAP voltage less than the limit defined in calibration with the engine idling; Intermittent Problem
Possible Causes
- •Poor connection at sensor
- •Faulty MAP sensor
Suggested Actions
- 1Using a DMM, measure the voltage potential across 5ref1 and 5V rtn1 at connector to check if voltage is >4.7 VDC
- 2Perform the On-Board (OBD) System Check
- 3If DTC 642 or 643 are present, troubleshoot those first
- 4Jumper the MAP circuit to Vref (5 VDC) in connector on harness to check if DST displays MAP voltage of 4.7 VDC or greater
- 5Disconnect wire harness header from ECM, carefully remove yellow lock from header at device output terminal, and check if resistance between MAP input at ECM header and signal at device is <5 ohms (probe on the side of terminal; do not insert probe or object into terminals to avoid spreading pins)
Related Power Solutions International Fault Codes
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Get a diagnosis walkthrough for 642 on your specific Power Solutions International unit — cited to the OEM manual, not a forum guess.
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