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DTC B1571: Reference Code Incompatibility (Immobilizer Control Module To ECM)

DTC detecting condition:

Reference codes between keyless access control module (model without ID code box) or ID code box (model with ID code box) and ECM do not match.

Trouble symptom:

Engine will not start.

CAUTION:

For replacement procedure of keyless access control module (model without ID code BOX) or ID code box (model with ID code BOX) or ECM, refer to the "REGISTRATION MANUAL FOR IMMOBILIZER" provided as a separate volume.
Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to KEYLESS ACCESS WITH PUSH BUTTON START (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION .

CHECK ECM .
Perform ECM registration. Refer to the "REGISTRATION MANUAL FOR IMMOBILIZER" provided as a separate volume.

Is ECM registration finished? And does the engine start?

Yes: ECM registration was not performed properly.

No: Go to 2.
REPLACE ECM .
1. Install the ECM from other normal operating vehicle (with push button start) which use same ECM to the vehicle to be diagnosed.
2. Perform ECM registration. Refer to the "REGISTRATION MANUAL FOR IMMOBILIZER" provided as a separate volume.
Is ECM registration finished? And does the engine start?

Yes: Replace the ECM. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>ENGINE CONTROL MODULE (ECM) . Install the ECM from other vehicle to the original vehicle.

No: Replace the keyless access control module (model without ID code box) Ref. to SECURITY AND LOCKS>KEYLESS ACCESS CONTROL MODULE . or the ID code box (model with ID code box). Ref. to SECURITY AND LOCKS>ID CODE BOX .