No Response From Engine Control Module - Mercedes-Benz Sprinter 2003 Manual

COMMUNICATION
Symptom:

*NO RESPONSE FROM ENGINE CONTROL MODULE

CHECK POWERS AND GROUNDS TO THE ENGINE CONTROL MODULE
K-ECM CIRCUIT SHORTED TO GROUND
K-ECM CIRCUIT SHORTED TO VOLTAGE
K-ECM CIRCUIT OPEN
ENGINE CONTROL MODULE
TEST
1 Turn the ignition off.
Disconnect the Engine Control Module harness connectors.
Check each power and ground circuit to the module.
Were any problems found?
Yes → Refer to the wiring diagrams located in the service information to
No
2 Turn the ignition off.
Disconnect the ECM harness connectors.
Disconnect the DRBIII from the DLC.
Measure the resistance between ground and the K-ECM circuit.
Is the resistance below 5.0 ohms?
Yes → Repair the K-ECM circuit for a short to ground.
No
3 Turn the ignition off.
Disconnect the DRBIII from the DLC.
Disconnect the ECM harness connectors.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-ECM circuit.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly?
Yes → Repair the K-ECM circuit for a short to voltage.
No
POSSIBLE CAUSES
ACTION
help isolate an open or shorted condition. Repair as necessary.
Perform ROAD TEST VERIFICATION - VER-2.
→ Go To 2
Perform ROAD TEST VERIFICATION - VER-2.
→ Go To 3
Perform ROAD TEST VERIFICATION - VER-2.
→ Go To 4
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APPLICABILITY
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