Diagnostic Procedure

WARNING: This page is about a different car, the 2005 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.

DTC B2139/P1260 DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY DTC USING WDS OR EQUIVALENT Are either U1900 or U0073, or both, displayed, by either the keyless control module or the PCM, or both.	Yes	Perform troubleshooting according to the corresponding DTC inspection. (See DTC U0073, U1900, U2516 .)
1		No	Go to the next step.
2	Perform procedures for when replacing the PCM only. (See IMMOBILIZER SYSTEM COMPONENT REPLACEMENT/KEY ADDITION AND CLEARING .) Using the registered key, turn the ignition switch to the ON position. Is the DTC displayed? SECURITY LIGHT: 23 WDS or equivalent: B2139/P1260	Yes	Replace the keyless control module and perform procedures for when replacing the keyless control module only. (See KEYLESS CONTROL MODULE REMOVAL/INSTALLATION .) (See IMMOBILIZER SYSTEM COMPONENT REPLACEMENT/KEY ADDITION AND CLEARING .) Go to the next step.
2		No	DTC troubleshooting completed.
3	Are any or all of the following DTCs displayed again? SECURITY LIGHT: 23 WDS or equivalent: B2139/P1260	Yes	Replace the PCM and perform procedures for when replacing the PCM only. (See PCM REMOVAL/INSTALLATION .) (See IMMOBILIZER SYSTEM COMPONENT REPLACEMENT/KEY ADDITION AND CLEARING .)
3		No	DTC troubleshooting completed.