DTC P1602 [MZR-CD (RF Turbo)]

BME010201600W08

DTC P1602

Immobilizer unit-PCM communication error

DETECTION CONDITION

• Command transmission from PCM to immobilizer unit exceeds limit.
• No response from immobilizer unit

POSSIBLE CAUSE

• Immobilizer unit malfunction
• Coil (immobilizer system) malfunction
• Key (transponder) malfunction
• Connector or terminal malfunction
• Open circuit in wiring between immobilizer unit terminal A and PCM terminal 54
• Open circuit in wiring between immobilizer unit terminal C and body GND
• Open circuit in wiring between immobilizer unit terminal D and coil terminal C
• Open circuit in wiring between immobilizer unit terminal F and coil terminal A
• Short to GND in wiring between immobilizer unit terminal A and PCM terminal 54
• Short to GND in wiring between immobilizer unit terminal D and coil terminal C
• Short to GND in wiring between immobilizer unit terminal F and coil terminal A
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Check for related Service Information availability.
• Is any related repair information available?
Yes
Perform repair or diagnosis according to available Service Information.
• If vehicle is not repaired, go to next step.
No
Go to next step.
2
VERIFY DTC P1602 DETECTED AGAIN
• Clear DTC from PCM memory using WDS or equivalent.
• Start engine.
• Is same DTC present?
Yes
Go to Step 10.
No
Go to next step.
3
INSPECT POOR CONNECTION OF IMMOBILIZER UNIT CONNECTOR
• Turn engine switch to OFF.
• Inspect for poor connection (damaged, pulled-out terminals, corrosion, etc.).
• Is there any malfunction?
Yes
Repair or replace suspected terminal, go to Step 19.
No
Go to next step.
4
INSPECT IMMOBILIZER UNIT GND CIRCUIT FOR OPEN
• Turn engine switch to OFF.
• Inspect continuity between immobilizer unit terminal C and body GND.
• Is there continuity?
Yes
Go to next step.
No
Repair or replace harness for open, go to Step 19.
5
INSPECT POOR CONNECTION OF COIL CONNECTOR
• Turn engine switch to OFF.
• Inspect for poor connection (damaged, pulled-out terminals, corrosion, etc.).
• Is there any malfunction?
Yes
Repair or replace suspected terminal, go to Step 19.
No
Go to next step.
6
INSPECT COIL FOR SHORT TO GND
• Turn engine switch to OFF.
• Inspect continuity between coil terminal A and body GND.
• Is there continuity?
Yes
Replace coil, go to Step 19.
No
Go to next step.
7
INSPECT COIL CIRCUIT FOR SHORT TO GND
• Turn engine switch to OFF.
• Inspect continuity between immobilizer unit terminal F and body GND.
• Is there continuity?
Yes
Repair or replace harness for short to GND, go to Step 19.
No
Go to next step.
8
INSPECT POOR CONNECTION OF PCM CONNECTOR
• Turn engine switch to OFF.
• Inspect for poor connection (damaged, pulled-out terminals, corrosion, etc.).
• Is there any malfunction?
Yes
Repair or replace suspected terminal, go to Step 19.
No
Go to next step.
9
INSPECT IMMOBILIZER UNIT SIGNAL CIRCUIT FOR OPEN
• Turn engine switch to OFF.
• Inspect continuity between immobilizer unit terminal A and PCM terminal 54.
• Is there continuity?
Yes
Go to step 19.
No
Repair or replace harness for open, go to Step 19.
10
CLASSIFY MALFUNCTION BY ANOTHER DETECTED DTCS
• Has DTC P1602 present?
Yes
Go to Step 14.
No
Go to next step.
11
INSPECT POOR CONNECTION OF COIL CONNECTOR
• Turn engine switch to OFF.
• Inspect for poor connection (damaged, pulled-out terminals, corrosion, etc.).
• Is there any malfunction?
Yes
Repair or replace suspected terminal, go to Step 19.
No
Go to next step.
12
INSPECT COIL FOR OPEN
• Turn engine switch to OFF.
• Inspect continuity between coil terminals A and C.
• Is there continuity?
Yes
Go to next step.
No
Replace coil, go to Step 19.
13
INSPECT COIL CIRCUIT FOR OPEN
• Turn engine switch to OFF.
• Inspect continuity between immobilizer unit terminals D and F.
• Is there continuity?
Yes
Go to Step 19.
No
Repair or replace harness for open, go to Step 19.
14
CLASSIFY MALFUNCTION BY OTHER DETECTED DTCS.
• Is immobilizer unit DTC 03 present?
Yes
Key does not have transponder, change to registered key.
Go to Step 19.
No
Go to next step.
15
CLASSIFY MALFUNCTION BY OTHER DETECTED DTCS.
• Is immobilizer unit DTC 01 present?
Yes
Key is not registered.
Reprogram key or use another registered key, go to next step.
No
Go to next step.
16
INSPECT POOR CONNECTION OF IMMOBILIZER UNIT CONNECTOR
• Turn engine switch to OFF.
• Inspect for poor connection (damaged, pulled-out terminals, corrosion, etc.).
• Is there any malfunction?
Yes
Repair or replace suspected terminal, go to next step.
No
Go to next step.
17
INSPECT IMMOBILIZER UNIT POWER CIRCUIT FOR OPEN
• Turn engine switch to OFF.
• Inspect voltage between immobilizer unit terminal J and body GND.
• Is voltage B+?
Yes
Go to next step.
No
Repair or replace harness for open, go to Step 19.
18
INSPECT IMMOBILIZER UNIT SIGNAL CIRCUIT FOR SHORT TO GND
• Turn engine switch to OFF.
• Inspect continuity between immobilizer unit terminal A and body GND.
• Is there continuity?
Yes
Repair or replace harness for short to GND, go to next step.
No
Go to next step.
19
VERIFY TROUBLESHOOTING OF DTC P1602 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear DTC from PCM memory using WDS or equivalent.
• Start engine.
• Is same DTC present?
Yes
Replace PCM, go to next step.
No
Go to next step.
20
VERIFY AFTER REPAIR PROCEDURE
• Perform "After Repair Procedure".
• Is there any DTC present?
Yes
Go to applicable DTC inspection.
No
Troubleshooting completed.