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Home >> Dodge and Ram >> 2017 >> Viper Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Communication Devices >> Communication - Non-DTC Based Diagnostics >> Diagnosis And Testing >> Scan Tool Does Not Communicate With Can IHS >> Possible Causes - Scan Tool Does Not Communicate With Can IHS
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Possible Causes - Scan Tool Does Not Communicate With Can IHS

This diagnostic will not have Diagnostic Trouble Codes to assist in determining no scan tool communication with the vehicle.

Possible Causes
FAULTY SCAN TOOL
DATA LINK CONNECTOR
CAN IHS (+) BUS CIRCUIT OPEN, SHORTED OR HIGH RESISTANCE
CAN IHS (-) BUS CIRCUIT OPEN, SHORTED OR HIGH RESISTANCE
POOR CONNECTION
STAR CONNECTOR
ANY MODULE ON THE CAN IHS BUS
NORMAL CAN CIRCUIT VOLTAGE TABLE

CIRCUIT NORMAL VOLTAGE VALUES
CAN IHS (-) 1.5 - 2.5 volts
CAN IHS (+) 2.5 - 3.5 volts
Difference Between CAN IHS (+) and CAN IHS (-) 0.5 volt