P0607

P0607 ECU INTERNAL PERFORMANCE

For complete wiring diagrams refer to Diagrams/Electrical.


Theory of Operation

The purpose of this test is to check the internal ECM fuel system diagnostic (ASIC) for proper operation by falsely inducing a failure and looking for the proper ECM response. At key off, the diagnostic overwrites injector on time and falsely cycles the injectors. If the internal ECM detection chip (ASIC) detects the firing and sets an error than the diagnostic passes. This diagnostic initially only runs at key off. If the diagnostic failed at the last key off cycle, then it will also run at the next cranking event. If the driver stalls the engine (manual transmission only) at the same moment that the key is turned off this diagnostic could fail. When the diagnostic fails, the ECM will flash the ETC lamp.

- When Monitored:

Initially at key off. If the diagnostic fails at last key off then it will also run at the next cranking event.

- Set Condition:

Induced failure does not set the internal ECM detection chip (ASIC) error.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test


1. INTERMITTENT CONDITION

Interview the customer. Ask if the truck was stalled at key off shortly before the ETC lamp started flashing.

Was the truck stalled at a recent key off event?

Yes

- Explain diagnostic to customer. Repair complete.

No

- Go To 2

2. ECM

Investigate truck for signs of a performance enhancement kit.

Are there signs that the customer has used a performance enhancement kit?

Yes

- Repair complete. Return vehicle to owner.

No

- Replace the ECM
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test