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DTC P1602 [L3]

BME010201600211

DTC P1602 | Immobilizer unit-PCM communication error
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DETECTION CONDITION | • Command transmission from the PCM to the immobilizer control module exceeds limit. • No response from immobilizer control module.
POSSIBLE CAUSE | • Immobilizer unit malfunction • Coil (immobilizer system) malfunction • Key (transponder) malfunction • PCM malfunction • Open circuit in wiring between immobilizer control module terminal A and PCM terminal 2Q
• Open circuit in wiring between immobilizer control module terminal C and body ground
• Open circuit in wiring between immobilizer control module terminal F and coil terminal A
• Open circuit in wiring between immobilizer control module terminal D and coil terminal C
• Short to ground circuit in wiring between immobilizer control module terminal A and PCM terminal 2Q
• Short to ground circuit in wiring between immobilizer control module terminal F and coil terminal A
• Short to ground circuit in wiring between immobilizer control module terminal D and coil terminal C
• Poor connection of immobilizer control module, PCM connector or coil
• Open circuit in wiring between immobilizer control module terminal J and battery positive terminal

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | PERFORM DTC CONFIRMATION PROCEDURE • Perform DTC CONFIRMATION PROCEDURE. (See DTC CONFIRMATION PROCEDURE [L3].) • Is same DTC present? | Yes | Go to the next step.
No | Intermittent concern exists. Go to INTERMITTENT CONCERN TROUBLESHOOTING procedure. (See INTERMITTENT CONCERN TROUBLESHOOTING [L3].)
2 | CLASSIFY NO DTC DETECTED OR SOME DTC DETECTED • Clear the DTC from the PCM memory using the WDS or equivalent. • Turn the ignition switch off and to the ON position (Engine off). • Has DTC P1624 been detected? | Yes | Go to step 10.
No | Go to the next step.
3 | INSPECT POOR CONNECTION OF IMMOBILIZER CONTROL MODULE CONNECTOR • Turn the ignition switch off. • Disconnect immobilizer control module connector. • Inspect for poor connection (damaged, pulled-out terminals, corrosion, etc.). • Is there any malfunction? | Yes | Repair or replace the terminals, then go to Step 19.
No | Go to the next step.
4 | INSPECT GROUND CIRCUIT OF IMMOBILIZER CONTROL MODULE FOR OPEN CIRCUIT • Measure the resistance between immobilizer control module terminal C (wiring harness-side) and body ground. • Is there continuity? | Yes | Go to the next step.
No | Repair or replace the wiring harness for open circuit, then go to Step 19.
5 | INSPECT COIL TERMINAL • Disconnect the coil connector. • Inspect for bent terminals. • Is there any malfunction? | Yes | Repair or replace the terminals, then go to Step 19.
No | Go to the next step.
6 | INSPECT COIL FOR SHORT CIRCUIT • Inspect for continuity between coil terminal A (part-side) and body ground. • Is there continuity? | Yes | Replace the coil, then go to Step 19.
No | Go to the next step.
7 | INSPECT COIL CIRCUIT FOR SHORT • Connect coil connector. • Inspect for continuity between immobilizer control module terminal F (wiring harness-side) and body ground. • Is there continuity? | Yes | Repair or replace the wiring harness for short circuit, then go to Step 19.
No | Go to the next step.
8 | INSPECT POOR CONNECTION OF PCM CONNECTOR • Disconnect the PCM connector. • Inspect for poor connection (such as damaged, pulled-out terminals, corrosion). • Is there any malfunction? | Yes | Repair or replace the wiring harness, then go to Step 19.
No | Go to the next step.
9 | INSPECT COMMUNICATION LINE FOR OPEN • Inspect for continuity between immobilizer control module terminal A (wiring harness-side) and PCM terminal 2Q. • Is there continuity? | Yes | Go to step 19.
No | Repair or replace the wiring harness for open circuit, then go to Step 19.
10 | CLASSIFY MALFUNCTION BY ANOTHER DETECTED DTCS • Has DTC P1602 detected? | Yes | Go to Step 14.
No | Go to the next step.
11 | INSPECT POOR CONNECTION OF COIL CONNECTOR • Disconnect the coil connector. • Inspect for poor connection (such as damaged/pulled-out terminals, corrosion). • Is there any malfunction? | Yes | Repair or replace the wiring harness, then go to Step 19.
No | Go to the next step.
12 | INSPECT COIL FOR OPEN CIRCUIT • Disconnect coil connector. • Measure the resistance between coil terminals (part-side). • Is there continuity? | Yes | Go to the next step.
No | Replace the coil, then go to Step 19.
13 | INSPECT COIL CIRCUIT FOR OPEN CIRCUIT • Connect the coil connector. • Measure the resistance between immobilizer connector F and D (wiring harness-side). • Is there continuity? | Yes | Go to Step 19.
No | Repair or replace the wiring harness for open circuit, then go to Step 19.
14 | CLASSIFY MALFUNCTION BY ANOTHER DETECTED DTCS. • Has immobilizer control module DTC 03 been detected? | Yes | Key has not transponder, change to registered key. Then go to Step 19.
No | Go to the next step.
15 | CLASSIFY MALFUNCTION BY ANOTHER DETECTED DTCS. • Has immobilizer control module DTC 01 detected? | Yes | Key that using for ignition is not registered. Reprogram key or using another registered key, then go to the next step.
No | Go to the next step.
16 | INSPECT POOR CONNECTION OF IMMOBILIZER CONTROL MODULE CONNECTOR • Turn the ignition switch off. • Disconnect immobilizer control module connector. • Inspect for poor connection (such as damaged/pulled-out terminals, corrosion). • Is there any malfunction? | Yes | Repair or replace the wiring harness, then go to the next step.
No | Go to the next step.
17 | INSPECT IMMOBILIZER CONTROL MODULE POWER CIRCUIT FOR OPEN CIRCUIT • Turn the ignition switch to the ON position (Engine off). • Measure the voltage between immobilizer connector J (wiring harness-side) and body ground. • Is the voltage B+? | Yes | Go to the next step.
No | Repair or replace the wiring harness for open circuit, then go to Step 19.
18 | INSPECT COMMUNICATION LINE FOR SHORT HARNESS • Measure the resistance between immobilizer control module terminal A (wiring harness-side) and body ground. • Is there continuity? | Yes | Repair or replace the wiring harness for short, then go to the next step.
No | Go to the next step.
19 | VERIFY TROUBLESHOOTING OF DTC P1602 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear the DTC from the PCM memory using the WDS or equivalent. • Perform KOEO self-test. (See KOEO/KOER SELF-TEST PROCEDURE [L3].)
• Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [L3].)
No | Go to the next step.
20 | VERIFY AFTER REPAIR PROCEDURE • Perform "After Repair Procedure". (See AFTER REPAIR PROCEDURE [L3].) • Is there any DTC present? | Yes | Go to the applicable DTC inspection. (See DTC TABLE [L3].)
No | Troubleshooting completed.