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DTC P1602 [MZR-CD (RF Turbo)]

BME010201600W08

DTC P1602 | Immobilizer unit-PCM communication error
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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
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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. (See PCM REMOVAL/INSTALLATION [MZR-CD (RF Turbo)].)
No | Go to next step.
20 | VERIFY AFTER REPAIR PROCEDURE • Perform "After Repair Procedure". (See AFTER REPAIR PROCEDURE [MZR-CD (RF Turbo)].) • Is there any DTC present? | Yes | Go to applicable DTC inspection. (See DTC TABLE [MZR-CD (RF Turbo)].)
No | Troubleshooting completed.