Mazda 6. Manual - part 353

ON-BOARD DIAGNOSTIC [IMMOBILIZER SYSTEM] 

T–161

T

End Of Sie

DTC TABLE

A6E817067000W02

Note

• Perform the following if the security light stays on:

— If engine stalls, go to symptom troubleshooting NO.11 “ENGINE STALLS/QUITS, ENGINE RUNS 

ROUGH, MISSES, BUCK/JERK, HESITATION/STUMBLE, SURGES” in. (See 

F–204 NO.11 ENGINE 

STALLS/QUITS, ENGINE RUNS ROUGH, MISSES, BUCK/JERK, HESITATION/STUMBLE, 
SURGES

.) 

— If engine won’t start, go to symptom troubleshooting NO.6 “CRANKS NORMALLY BUT WILL NOT 

START” in. (See 

F–195 NO.6 CRANKS NORMALLY BUT WILL NOT START

.)

— If engine condition is normal but light stays on, inspect for continuity between the following wiring 

harness and body ground: security light and PCM connector terminal 2W. Repair or replace the wiring 
harness.

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PID/DATA MONITOR TABLE

A6E817067000W00

DTC 

Description

Page

Security 

light

Security light flashing 

pattern

WDS or 

equivalent

11

B1681

Coil signal is not received.

(See 

T–162 SECURITY LIGHT: 

DTC 11 (WDS OR 
EQUIVALENT: DTC B1681)

)

12

B2103

Coil failure.

(See 

T–163 SECURITY LIGHT: 

DTC 12 (WDS OR 
EQUIVALENT: DTC B2103)

)

13

B1600

ID number signal is not 
received.

(See 

T–163 SECURITY LIGHT: 

DTC 13 (WDS OR 
EQUIVALENT: DTC B1600)

)

B2431

Transponder programming 
failure.

(See 

T–164 SECURITY LIGHT: 

DTC 13 (WDS OR 
EQUIVALENT: DTC B2431)

)

14

B1602

PCM received invalid format of 
ID number from transponder.

(See 

T–164 SECURITY LIGHT: 

DTC 14 (WDS OR 
EQUIVALENT: DTC B1602)

)

15

B1601

PCM received incorrect ID 
number from key 
(transponder).

(See 

T–164–1 SECURITY 

LIGHT: DTC 15 (WDS OR 
EQUIVALENT: DTC B1601)

)

21

B1213

Number of valid keys is below 
minimum.

(See 

T–164–1 SECURITY 

LIGHT: DTC 21 (WDS OR 
EQUIVALENT: DTC B1213)

)

—

—

B1342

PCM is defective.

(See 

T–164–2 SECURITY 

LIGHT: DTC - (WDS OR 
EQUIVALENT: DTC B1342)

)

PID mane (Description)

Unit

Specification

PCM terminal

NUMKEYS
 (Number of key stored in module)

–

Number of registered keys: 0—8

–

T–162

ON-BOARD DIAGNOSTIC [IMMOBILIZER SYSTEM] 

End Of Sie

SECURITY LIGHT: DTC 11 (WDS OR EQUIVALENT: DTC B1681)

A6E817067000W03

Diagnostic procedure

DTC 11 (B1681) Coil signal is not received.

POSSIBLE 

CAUSE

• Defective wiring harness

• Defective coil

• Defective PCM

COIL 

HARNESS SIDE CONNECTOR

A

B

C

D

PCM

HARNESS SIDE CONNECTOR

2T 2Q

STEP

INSPECTION

ACTION

1

INSPECT POWER SUPPLY CIRCUIT OF COIL

• Disconnect coil connector.

• Turn ignition switch to ON position.

• Measure voltage at terminal D of coil 

connector.

• Is voltage more than 8 V?

Yes

Go to next step.

No

Repair wiring harness.

2

INSPECT WIRING HARNESS BETWEEN COIL 
AND GROUND

• Turn ignition switch to LOCK position.

• Inspect wiring harness between coil 

connector terminal C and ground for 
following.
— Short to power supply
— Open circuit

• Is wiring harness okay?

Yes

Go to next step.

No

Repair wiring harness.

3

INSPECT COIL INPUT SIGNAL CIRCUIT

• Connect coil connector.

• Turn ignition switch to ON position.

• Measure voltage at terminal B of coil 

connector.

• Is voltage more than 8 V?

Yes

Go to Step 7.

No

Go to next step.

4

INSPECT COIL INPUT SIGNAL CIRCUIT

• Turn ignition switch to LOCK position.

• Disconnect PCM connector.

• Turn ignition switch to ON position.

• Measure voltage at terminal 2T of PCM 

connector.

• Is voltage more than 8 V?

Yes

Replace PCM and reprogram immobilizer system.
(See 

T–90 IMMOBILIZER SYSTEM REPROGRAM 

PROCEDURE

)

No

Go to next step.

5

INSPECT COMMUNICATION CIRCUIT 
(INPUT) FOR CONTINUITY

• Turn ignition switch to LOCK position.

• Disconnect coil and PCM connectors.

• Is there continuity between coil connector 

terminal B and PCM connector terminal 2T?

Yes

Go to next step.

No

Repair wiring harness.

6

INSPECT COIL INPUT SIGNAL CIRCUIT

• Measure resistance between coil connector 

terminal B and ground.

• Is resistance more than 10 kilohms?

Yes

Replace coil.
(See 

T–90 COIL REMOVAL/INSTALLATION

)

No

Repair wiring harness.

7

INSPECT COIL OUTPUT SIGNAL CIRCUIT

• Connect coil and PCM connectors.

• Turn ignition switch to ON position.

• Measure voltage at terminal A of coil 

connector.

• Is voltage more than 8 V?

Yes

Replace coil.
(See 

T–90 COIL REMOVAL/INSTALLATION

)

No

Go to next step.

ON-BOARD DIAGNOSTIC [IMMOBILIZER SYSTEM] 

T–163

T

End Of Sie

SECURITY LIGHT: DTC 12 (WDS OR EQUIVALENT: DTC B2103)

A6E817067000W04

Diagnostic procedure

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SECURITY LIGHT: DTC 13 (WDS OR EQUIVALENT: DTC B1600)

A6E817067000W05

Diagnostic procedure

8

INSPECT COIL OUTPUT SIGNAL CIRCUIT

• Turn ignition switch to LOCK position.

• Disconnect coil connector.

• Turn ignition switch to ON position.

• Measure voltage at terminal A of coil 

connector.

• Is voltage more than 8 V?

Yes

Replace coil.
(See 

T–90 COIL REMOVAL/INSTALLATION

)

No

Go to next step.

9

INSPECT COMMUNICATION CIRCUIT 
(OUTPUT) FOR CONTINUITY

• Turn ignition switch to LOCK position.

• Disconnect PCM connector.

• Is there continuity between coil connector 

terminal A and PCM connector terminal 2Q?

Yes

Go to next step.

No

Repair wiring harness.

10

INSPECT COIL OUTPUT SIGNAL CIRCUIT

• Measure resistance between PCM connector 

terminal 2Q and ground.

• Is resistance more than 10 kilohms?

Yes

Replace PCM and reprogram immobilizer system.
(See 

T–90 IMMOBILIZER SYSTEM REPROGRAM 

PROCEDURE

)

No

Repair wiring harness.

STEP

INSPECTION

ACTION

DTC 12 (B2103) Coil failure.

POSSIBLE 

CAUSE

• Defective Coil

• Poor connection of coil connector

STEP

INSPECTION

ACTION

—

INSPECT CONNECTOR CONNECTION

• Is connector of coil and PCM connected 

securely?

Yes

Replace coil.
(See 

T–90 COIL REMOVAL/INSTALLATION

)

No

Connect connector securely.

DTC 13 (B1600) ID number is not received.

POSSIBLE 

CAUSE

• No transponder in the key

• Defective transponder in the key (ID number is not output.)

• Defective coil

• Defective PCM

STEP

INSPECTION

ACTION

1

VERIFY DTC USING SST

• Does SST (WDS or equivalent) indicate DTC 

B1600?

Yes

Go to Step 3.

No

Go to next step.

2

VERIFY DTC USING SST

• Does SST (WDS or equivalent) indicate DTC 

B2431?

Yes

Go to SECURITY LIGHT: DTC 13 (WDS OR EQUIVALENT: 
B2431).

No

Go to next step.

3

VERIFY VALID KEY

• Is there any key, other than the one that 

caused displayed DTC, which can start the 
engine?

Yes

Go to Step 5.

No

Go to next step.

4

VERIFY WHETHER MALFUNCTION IS IN 
COIL OR KEY

• Using SST (WDS or equivalent) register an 

additional key.
(See 

T–90 IMMOBILIZER SYSTEM 

REPROGRAM PROCEDURE

)

• Using registered key, turn ignition switch to 

ON position.

• Does SST (WDS or equivalent) indicate DTC 

B1600 again?

Yes

Replace coil, then go to step 6.
(See 

T–90 COIL REMOVAL/INSTALLATION

)

No

• Dispose of defective key.

• Duplicate key if necessary.

(See 

T–90 IMMOBILIZER SYSTEM REPROGRAM 

PROCEDURE

)

T–164

ON-BOARD DIAGNOSTIC [IMMOBILIZER SYSTEM] 

End Of Sie

SECURITY LIGHT: DTC 13 (WDS OR EQUIVALENT: DTC B2431)

A6E817067000W06

Diagnostic procedure

End Of Sie

SECURITY LIGHT: DTC 14 (WDS OR EQUIVALENT: DTC B1602)

A6E817067000W07

Diagnostic procedure

End Of Sie

5

VERIFY WHETHER MALFUNCTION IS IN 

COIL OR KEY

• Using any other valid key, turn ignition switch 

to ON position.

• Does SST (WDS or equivalent) indicate DTC 

B1600 again?

Yes

Replace coil, then go to next step.
(See 

T–90 COIL REMOVAL/INSTALLATION

)

No

• Dispose of defective key.

• Duplicate key if necessary.

(See 

T–90 IMMOBILIZER SYSTEM REPROGRAM 

PROCEDURE

)

6

INSPECT PCM

• Using registered key, turn ignition switch to 

ON position.

• Does SST (WDS or equivalent) indicate DTC 

B1600 again?

Yes

Replace PCM and reprogram immobilizer system.
(See 

T–90 IMMOBILIZER SYSTEM REPROGRAM 

PROCEDURE

)

No

Troubleshooting is completed.

STEP

INSPECTION

ACTION

DTC 13 (B2431) ID number programing failure.

POSSIBLE 

CAUSE

• The procedure fails to program the transponder into PCM

STEP

INSPECTION

ACTION

1

VERIFY DTC USING SST

• Does SST (WDS or equivalent) indicate DTC 

B2431?

Yes

Go to Step 3.

No

Go to next step.

2

VERIFY DTC USING SST

• Does SST (WDS or equivalent) indicate DTC 

B1600?

Yes

Go to SECURITY LIGHT: DTC 13 (WDS OR EQUIVALENT: 
B1600).

No

Go to next step.

3

INSPECT PCM

• Erase key ID number using SST (WDS) and 

register key ID number.
(See 

T–90 IMMOBILIZER SYSTEM 

REPROGRAM PROCEDURE

)

• Clear DTC with SST (WDS or equivalent).

• Does SST (WDS or equivalent) indicate DTC 

B2431 again?

Yes

Replace PCM and reprogram immobilizer system.
(See 

T–90 IMMOBILIZER SYSTEM REPROGRAM 

PROCEDURE

)

No

Troubleshooting is completed.

DTC 14 (B1602) PCM received invalid format of ID number from key (transponder)

POSSIBLE 

CAUSE

• Defective transponder in the key

• Defective coil

• Defective PCM

STEP

INSPECTION

ACTION

1

INSPECT FOR OTHER PROPER KEYS

• Using any other valid key, turn ignition switch 

to ON position.

• Does security light or SST (WDS or 

equivalent) indicate DTC 14 (B1602) again?

Yes

Replace coil, then go to next step.
(See 

T–90 COIL REMOVAL/INSTALLATION

)

No

• Dispose of defective key.

• Duplicate key if necessary.

(See 

T–90 IMMOBILIZER SYSTEM REPROGRAM 

PROCEDURE

)

2

INSPECT PCM

• Turn ignition switch to ON position with the 

registered key.

• Does security light or SST (WDS or 

equivalent) indicate DTC 14 (B1602) again?

Yes

Replace PCM and reprogram immobilizer system.
(See 

T–90 IMMOBILIZER SYSTEM REPROGRAM 

PROCEDURE

)

No

Troubleshooting is completed.