Diagnostic Procedure

DTC B1238:16 DIAGNOSTIC PROCEDURE

Step	Inspection		Action
1	VERIFY PCM DTCs Retrieve the PCM DTCs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .) Are any DTCs displayed?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .)
1		No	Go to the next step.
2	INSPECT BATTERY Inspect the battery. (See BATTERY INSPECTION .) Is the battery normal?	Yes	Go to the next step.
2		No	Recharge or replace the battery, then go to Step 6. (See BATTERY RECHARGING .) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
3	INSPECT GENERATOR Inspect the generator. (See GENERATOR INSPECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Is the generator normal?	Yes	Go to the next step.
3		No	Replace the generator, then go to Step 6. (See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
4	INSPECT TUNER AND AMP UNIT (TAU) CONNECTOR CONDITION Switch the ignition off. Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .) Disconnect the tuner and amp unit (TAU) connector. Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. Is the connector normal?	Yes	Go to the next step.
4		No	Repair or replace the connector, then go to Step 6.
5	VERIFY TUNER AND AMP UNIT (TAU) POWER SUPPLY VOLTAGE Verify that the tuner and amp unit (TAU) connector is disconnected. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .) Switch the ignition ON (engine off or on). Measure the voltage at tuner and amp unit (TAU) terminal 2B (wiring harness-side). Is the voltage 10 V or more?	Yes	Go to the next step.
5		No	Inspect the AUDIO1 15 A fuse, AUDIO 30 A fuse. If the fuse is blown: Refer to the wiring diagram and verify if there is a common connector between AUDIO 30 A fuse and tuner and amp unit (TAU) terminal 2B. If there is a common connector: Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location. Repair or replace the malfunctioning location. If there is no common connector: Repair or replace the wiring harness which is shorted to ground. Replace the fuse. If the fuse is damaged: Replace the fuse. If the fuse is normal: Refer to the wiring diagram and verify if there is a common connector between battery positive terminal and tuner and amp unit (TAU) terminal 2B. If there is a common connector: Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for an open circuit to determine the malfunctioning location. Repair or replace the malfunctioning location. If there is no common connector: Repair or replace the wiring harness which has an open circuit. Go to the next step.
6	VERIFY THAT REPAIRS HAVE BEEN COMPLETED Always reconnect all disconnected connectors. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .) Clear the DTC for the connectivity master unit (CMU) using the M-MDS. (See CLEARING DTC [CONNECTIVITY MASTER UNIT] .) Switch the ignition ON (engine off or on) and wait for 17 s or more. Retrieve the connectivity master unit (CMU) DTCs using the M-MDS. (See DTC INSPECTION [CONNECTIVITY MASTER UNIT] .) Is the same DTC displayed?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the tuner and amp unit (TAU). (See TUNER AND AMP UNIT (TAU) REMOVAL/INSTALLATION .) Go to the next step.
6		No	Go to the next step.
7	VERIFY IF OTHER DTCs DISPLAYED Are any other DTCs displayed?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [CONNECTIVITY MASTER UNIT] .)
7		No	DTC troubleshooting completed.