P0650
MIL Control Circuit/Open
Causes
- Blown fuse or fusible link for instrument cluster/PCM power
- Open or damaged wiring between PCM and instrument cluster (broken conductor, chafe, connector corrosion)
- Faulty instrument cluster MIL bulb or LED assembly
- Poor or missing ground at instrument cluster or PCM
- Faulty PCM/ECM MIL driver transistor or internal open circuit
- Aftermarket equipment or harness modification interrupting the MIL circuit
Symptoms
- Check Engine Light (MIL) does not illuminate during key ON bulb check
- MIL remains off when a monitored fault is present
- MIL may be intermittent or only illuminate under vibration/wiring movement
- No MIL illumination during scan-tool commanded lamp ON test
What to check
- Read and record DTC(s) with a scan tool and note freeze-frame/live data
- Visual inspection of instrument cluster area, wiring harness, and connectors for damage or corrosion
- Verify instrument panel fuses and fusible links are present and good
- Perform key ON engine OFF (KOEO) MIL bulb check: MIL should illuminate for a few seconds
- Use scan tool to command MIL ON/OFF and observe response
- Backprobe and measure voltage/continuity at the MIL connector, PCM MIL output pin, and ground
Signal parameters
- Key ON (engine off) MIL lamp: lamp circuit should show battery voltage at lamp connector when lamp is OFF (~11–13.5 V depending on battery state)
- When MIL is commanded ON by PCM: the PCM typically pulls the lamp circuit to ground — measured voltage at PCM output should be low (near 0 V) when ON
- Continuity between PCM MIL output pin and instrument cluster MIL pin: low resistance expected (typically
- Open circuit reading is effectively infinite resistance or no continuity
- Connector terminal voltages: good ground
Diagnostic algorithm
- Connect a scan tool, record P0650 and any related codes; clear codes and see if P0650 returns.
- Verify MIL behavior: with key ON (engine off) confirm MIL lights for bulb-check seconds. If it does, the lamp and cluster circuit likely work — issue may be intermittent or PCM-side.
- Check fuses and fusible links for instrument cluster and PCM power/ignition circuits; replace any blown fuses and retest.
- Perform a visual inspection of harness and connectors from PCM to instrument cluster — look for pin corrosion, bent/ pushed-out terminals, chafing, or previous repairs.
- Use a multimeter to backprobe the MIL lamp connector at the cluster: measure for battery voltage with lamp OFF and low resistance to ground when the scanner commands MIL ON. Record voltages.
- Backprobe the PCM MIL output pin and compare to cluster side. If PCM output does not change when commanded but cluster side does (or vice versa), narrow fault to harness/connector between them.
- Check continuity and resistance of the MIL circuit between PCM and cluster. Repair any open/ high-resistance sections (repair wiring, replace connectors or pigtails as needed).
- If wiring and lamp check good, inspect/bench-test instrument cluster lamp/LED circuitry or substitute a known-good cluster to verify.
- Only consider replacement of the PCM/ECM after fully diagnosing and verifying that the PCM MIL driver is faulty and all wiring/cluster options have been ruled out.
- After repair, clear codes, perform KOEO MIL check and use scan tool to command MIL ON/OFF; road test and re-scan to confirm code does not return.
Likely causes
- Open/disconnected MIL lamp connector or broken wire between PCM and cluster
- Failed MIL lamp (bulb or LED) or failed instrument cluster circuit
- Blown fuse protecting MIL/cluster circuit
- PCM/ECM MIL output driver failed (less common)
Fault status
Similar codes
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Workshop ManualP0650
- Malfunction Indicator Lamp Circuit Malfunction (MIL)
Causes
- Blown fuse or fusible link for instrument cluster/PCM power
- Open or damaged wiring between PCM and instrument cluster (broken conductor, chafe, connector corrosion)
- Faulty instrument cluster MIL bulb or LED assembly
- Poor or missing ground at instrument cluster or PCM
- Faulty PCM/ECM MIL driver transistor or internal open circuit
- Aftermarket equipment or harness modification interrupting the MIL circuit
Symptoms
- Check Engine Light (MIL) does not illuminate during key ON bulb check
- MIL remains off when a monitored fault is present
- MIL may be intermittent or only illuminate under vibration/wiring movement
- No MIL illumination during scan-tool commanded lamp ON test
What to check
- Read and record DTC(s) with a scan tool and note freeze-frame/live data
- Visual inspection of instrument cluster area, wiring harness, and connectors for damage or corrosion
- Verify instrument panel fuses and fusible links are present and good
- Perform key ON engine OFF (KOEO) MIL bulb check: MIL should illuminate for a few seconds
- Use scan tool to command MIL ON/OFF and observe response
- Backprobe and measure voltage/continuity at the MIL connector, PCM MIL output pin, and ground
Signal parameters
- Key ON (engine off) MIL lamp: lamp circuit should show battery voltage at lamp connector when lamp is OFF (~11–13.5 V depending on battery state)
- When MIL is commanded ON by PCM: the PCM typically pulls the lamp circuit to ground — measured voltage at PCM output should be low (near 0 V) when ON
- Continuity between PCM MIL output pin and instrument cluster MIL pin: low resistance expected (typically
- Open circuit reading is effectively infinite resistance or no continuity
- Connector terminal voltages: good ground
Diagnostic algorithm
- Connect a scan tool, record P0650 and any related codes; clear codes and see if P0650 returns.
- Verify MIL behavior: with key ON (engine off) confirm MIL lights for bulb-check seconds. If it does, the lamp and cluster circuit likely work — issue may be intermittent or PCM-side.
- Check fuses and fusible links for instrument cluster and PCM power/ignition circuits; replace any blown fuses and retest.
- Perform a visual inspection of harness and connectors from PCM to instrument cluster — look for pin corrosion, bent/ pushed-out terminals, chafing, or previous repairs.
- Use a multimeter to backprobe the MIL lamp connector at the cluster: measure for battery voltage with lamp OFF and low resistance to ground when the scanner commands MIL ON. Record voltages.
- Backprobe the PCM MIL output pin and compare to cluster side. If PCM output does not change when commanded but cluster side does (or vice versa), narrow fault to harness/connector between them.
- Check continuity and resistance of the MIL circuit between PCM and cluster. Repair any open/ high-resistance sections (repair wiring, replace connectors or pigtails as needed).
- If wiring and lamp check good, inspect/bench-test instrument cluster lamp/LED circuitry or substitute a known-good cluster to verify.
- Only consider replacement of the PCM/ECM after fully diagnosing and verifying that the PCM MIL driver is faulty and all wiring/cluster options have been ruled out.
- After repair, clear codes, perform KOEO MIL check and use scan tool to command MIL ON/OFF; road test and re-scan to confirm code does not return.
Likely causes
- Open/disconnected MIL lamp connector or broken wire between PCM and cluster
- Failed MIL lamp (bulb or LED) or failed instrument cluster circuit
- Blown fuse protecting MIL/cluster circuit
- PCM/ECM MIL output driver failed (less common)
Fault status
Similar codes
P0650
Malfunction Indicator Lamp (MIL) Control Circuit
Causes
- Blown fuse or fusible link for instrument cluster/PCM power
- Open or damaged wiring between PCM and instrument cluster (broken conductor, chafe, connector corrosion)
- Faulty instrument cluster MIL bulb or LED assembly
- Poor or missing ground at instrument cluster or PCM
- Faulty PCM/ECM MIL driver transistor or internal open circuit
- Aftermarket equipment or harness modification interrupting the MIL circuit
Symptoms
- Check Engine Light (MIL) does not illuminate during key ON bulb check
- MIL remains off when a monitored fault is present
- MIL may be intermittent or only illuminate under vibration/wiring movement
- No MIL illumination during scan-tool commanded lamp ON test
What to check
- Read and record DTC(s) with a scan tool and note freeze-frame/live data
- Visual inspection of instrument cluster area, wiring harness, and connectors for damage or corrosion
- Verify instrument panel fuses and fusible links are present and good
- Perform key ON engine OFF (KOEO) MIL bulb check: MIL should illuminate for a few seconds
- Use scan tool to command MIL ON/OFF and observe response
- Backprobe and measure voltage/continuity at the MIL connector, PCM MIL output pin, and ground
Signal parameters
- Key ON (engine off) MIL lamp: lamp circuit should show battery voltage at lamp connector when lamp is OFF (~11–13.5 V depending on battery state)
- When MIL is commanded ON by PCM: the PCM typically pulls the lamp circuit to ground — measured voltage at PCM output should be low (near 0 V) when ON
- Continuity between PCM MIL output pin and instrument cluster MIL pin: low resistance expected (typically
- Open circuit reading is effectively infinite resistance or no continuity
- Connector terminal voltages: good ground
Diagnostic algorithm
- Connect a scan tool, record P0650 and any related codes; clear codes and see if P0650 returns.
- Verify MIL behavior: with key ON (engine off) confirm MIL lights for bulb-check seconds. If it does, the lamp and cluster circuit likely work — issue may be intermittent or PCM-side.
- Check fuses and fusible links for instrument cluster and PCM power/ignition circuits; replace any blown fuses and retest.
- Perform a visual inspection of harness and connectors from PCM to instrument cluster — look for pin corrosion, bent/ pushed-out terminals, chafing, or previous repairs.
- Use a multimeter to backprobe the MIL lamp connector at the cluster: measure for battery voltage with lamp OFF and low resistance to ground when the scanner commands MIL ON. Record voltages.
- Backprobe the PCM MIL output pin and compare to cluster side. If PCM output does not change when commanded but cluster side does (or vice versa), narrow fault to harness/connector between them.
- Check continuity and resistance of the MIL circuit between PCM and cluster. Repair any open/ high-resistance sections (repair wiring, replace connectors or pigtails as needed).
- If wiring and lamp check good, inspect/bench-test instrument cluster lamp/LED circuitry or substitute a known-good cluster to verify.
- Only consider replacement of the PCM/ECM after fully diagnosing and verifying that the PCM MIL driver is faulty and all wiring/cluster options have been ruled out.
- After repair, clear codes, perform KOEO MIL check and use scan tool to command MIL ON/OFF; road test and re-scan to confirm code does not return.
Likely causes
- Open/disconnected MIL lamp connector or broken wire between PCM and cluster
- Failed MIL lamp (bulb or LED) or failed instrument cluster circuit
- Blown fuse protecting MIL/cluster circuit
- PCM/ECM MIL output driver failed (less common)
Fault status
Similar codes
P0650
Malfunction Indicator Lamp (MIL) Control Circuit
Causes
- Blown fuse or fusible link for instrument cluster/PCM power
- Open or damaged wiring between PCM and instrument cluster (broken conductor, chafe, connector corrosion)
- Faulty instrument cluster MIL bulb or LED assembly
- Poor or missing ground at instrument cluster or PCM
- Faulty PCM/ECM MIL driver transistor or internal open circuit
- Aftermarket equipment or harness modification interrupting the MIL circuit
Symptoms
- Check Engine Light (MIL) does not illuminate during key ON bulb check
- MIL remains off when a monitored fault is present
- MIL may be intermittent or only illuminate under vibration/wiring movement
- No MIL illumination during scan-tool commanded lamp ON test
What to check
- Read and record DTC(s) with a scan tool and note freeze-frame/live data
- Visual inspection of instrument cluster area, wiring harness, and connectors for damage or corrosion
- Verify instrument panel fuses and fusible links are present and good
- Perform key ON engine OFF (KOEO) MIL bulb check: MIL should illuminate for a few seconds
- Use scan tool to command MIL ON/OFF and observe response
- Backprobe and measure voltage/continuity at the MIL connector, PCM MIL output pin, and ground
Signal parameters
- Key ON (engine off) MIL lamp: lamp circuit should show battery voltage at lamp connector when lamp is OFF (~11–13.5 V depending on battery state)
- When MIL is commanded ON by PCM: the PCM typically pulls the lamp circuit to ground — measured voltage at PCM output should be low (near 0 V) when ON
- Continuity between PCM MIL output pin and instrument cluster MIL pin: low resistance expected (typically
- Open circuit reading is effectively infinite resistance or no continuity
- Connector terminal voltages: good ground
Diagnostic algorithm
- Connect a scan tool, record P0650 and any related codes; clear codes and see if P0650 returns.
- Verify MIL behavior: with key ON (engine off) confirm MIL lights for bulb-check seconds. If it does, the lamp and cluster circuit likely work — issue may be intermittent or PCM-side.
- Check fuses and fusible links for instrument cluster and PCM power/ignition circuits; replace any blown fuses and retest.
- Perform a visual inspection of harness and connectors from PCM to instrument cluster — look for pin corrosion, bent/ pushed-out terminals, chafing, or previous repairs.
- Use a multimeter to backprobe the MIL lamp connector at the cluster: measure for battery voltage with lamp OFF and low resistance to ground when the scanner commands MIL ON. Record voltages.
- Backprobe the PCM MIL output pin and compare to cluster side. If PCM output does not change when commanded but cluster side does (or vice versa), narrow fault to harness/connector between them.
- Check continuity and resistance of the MIL circuit between PCM and cluster. Repair any open/ high-resistance sections (repair wiring, replace connectors or pigtails as needed).
- If wiring and lamp check good, inspect/bench-test instrument cluster lamp/LED circuitry or substitute a known-good cluster to verify.
- Only consider replacement of the PCM/ECM after fully diagnosing and verifying that the PCM MIL driver is faulty and all wiring/cluster options have been ruled out.
- After repair, clear codes, perform KOEO MIL check and use scan tool to command MIL ON/OFF; road test and re-scan to confirm code does not return.
Likely causes
- Open/disconnected MIL lamp connector or broken wire between PCM and cluster
- Failed MIL lamp (bulb or LED) or failed instrument cluster circuit
- Blown fuse protecting MIL/cluster circuit
- PCM/ECM MIL output driver failed (less common)
Fault status
Similar codes
P0650
Failure in the control circuit of the malfunction indicator lamp
Causes
- Blown fuse or fusible link for instrument cluster/PCM power
- Open or damaged wiring between PCM and instrument cluster (broken conductor, chafe, connector corrosion)
- Faulty instrument cluster MIL bulb or LED assembly
- Poor or missing ground at instrument cluster or PCM
- Faulty PCM/ECM MIL driver transistor or internal open circuit
- Aftermarket equipment or harness modification interrupting the MIL circuit
Symptoms
- Check Engine Light (MIL) does not illuminate during key ON bulb check
- MIL remains off when a monitored fault is present
- MIL may be intermittent or only illuminate under vibration/wiring movement
- No MIL illumination during scan-tool commanded lamp ON test
What to check
- Read and record DTC(s) with a scan tool and note freeze-frame/live data
- Visual inspection of instrument cluster area, wiring harness, and connectors for damage or corrosion
- Verify instrument panel fuses and fusible links are present and good
- Perform key ON engine OFF (KOEO) MIL bulb check: MIL should illuminate for a few seconds
- Use scan tool to command MIL ON/OFF and observe response
- Backprobe and measure voltage/continuity at the MIL connector, PCM MIL output pin, and ground
Signal parameters
- Key ON (engine off) MIL lamp: lamp circuit should show battery voltage at lamp connector when lamp is OFF (~11–13.5 V depending on battery state)
- When MIL is commanded ON by PCM: the PCM typically pulls the lamp circuit to ground — measured voltage at PCM output should be low (near 0 V) when ON
- Continuity between PCM MIL output pin and instrument cluster MIL pin: low resistance expected (typically
- Open circuit reading is effectively infinite resistance or no continuity
- Connector terminal voltages: good ground
Diagnostic algorithm
- Connect a scan tool, record P0650 and any related codes; clear codes and see if P0650 returns.
- Verify MIL behavior: with key ON (engine off) confirm MIL lights for bulb-check seconds. If it does, the lamp and cluster circuit likely work — issue may be intermittent or PCM-side.
- Check fuses and fusible links for instrument cluster and PCM power/ignition circuits; replace any blown fuses and retest.
- Perform a visual inspection of harness and connectors from PCM to instrument cluster — look for pin corrosion, bent/ pushed-out terminals, chafing, or previous repairs.
- Use a multimeter to backprobe the MIL lamp connector at the cluster: measure for battery voltage with lamp OFF and low resistance to ground when the scanner commands MIL ON. Record voltages.
- Backprobe the PCM MIL output pin and compare to cluster side. If PCM output does not change when commanded but cluster side does (or vice versa), narrow fault to harness/connector between them.
- Check continuity and resistance of the MIL circuit between PCM and cluster. Repair any open/ high-resistance sections (repair wiring, replace connectors or pigtails as needed).
- If wiring and lamp check good, inspect/bench-test instrument cluster lamp/LED circuitry or substitute a known-good cluster to verify.
- Only consider replacement of the PCM/ECM after fully diagnosing and verifying that the PCM MIL driver is faulty and all wiring/cluster options have been ruled out.
- After repair, clear codes, perform KOEO MIL check and use scan tool to command MIL ON/OFF; road test and re-scan to confirm code does not return.
Likely causes
- Open/disconnected MIL lamp connector or broken wire between PCM and cluster
- Failed MIL lamp (bulb or LED) or failed instrument cluster circuit
- Blown fuse protecting MIL/cluster circuit
- PCM/ECM MIL output driver failed (less common)
Fault status
Similar codes
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Workshop ManualP0650
Malfunction Indicator Lamp (MIL) Control Circuit Malfunction
Causes
- Blown fuse or fusible link for instrument cluster/PCM power
- Open or damaged wiring between PCM and instrument cluster (broken conductor, chafe, connector corrosion)
- Faulty instrument cluster MIL bulb or LED assembly
- Poor or missing ground at instrument cluster or PCM
- Faulty PCM/ECM MIL driver transistor or internal open circuit
- Aftermarket equipment or harness modification interrupting the MIL circuit
Symptoms
- Check Engine Light (MIL) does not illuminate during key ON bulb check
- MIL remains off when a monitored fault is present
- MIL may be intermittent or only illuminate under vibration/wiring movement
- No MIL illumination during scan-tool commanded lamp ON test
What to check
- Read and record DTC(s) with a scan tool and note freeze-frame/live data
- Visual inspection of instrument cluster area, wiring harness, and connectors for damage or corrosion
- Verify instrument panel fuses and fusible links are present and good
- Perform key ON engine OFF (KOEO) MIL bulb check: MIL should illuminate for a few seconds
- Use scan tool to command MIL ON/OFF and observe response
- Backprobe and measure voltage/continuity at the MIL connector, PCM MIL output pin, and ground
Signal parameters
- Key ON (engine off) MIL lamp: lamp circuit should show battery voltage at lamp connector when lamp is OFF (~11–13.5 V depending on battery state)
- When MIL is commanded ON by PCM: the PCM typically pulls the lamp circuit to ground — measured voltage at PCM output should be low (near 0 V) when ON
- Continuity between PCM MIL output pin and instrument cluster MIL pin: low resistance expected (typically
- Open circuit reading is effectively infinite resistance or no continuity
- Connector terminal voltages: good ground
Diagnostic algorithm
- Connect a scan tool, record P0650 and any related codes; clear codes and see if P0650 returns.
- Verify MIL behavior: with key ON (engine off) confirm MIL lights for bulb-check seconds. If it does, the lamp and cluster circuit likely work — issue may be intermittent or PCM-side.
- Check fuses and fusible links for instrument cluster and PCM power/ignition circuits; replace any blown fuses and retest.
- Perform a visual inspection of harness and connectors from PCM to instrument cluster — look for pin corrosion, bent/ pushed-out terminals, chafing, or previous repairs.
- Use a multimeter to backprobe the MIL lamp connector at the cluster: measure for battery voltage with lamp OFF and low resistance to ground when the scanner commands MIL ON. Record voltages.
- Backprobe the PCM MIL output pin and compare to cluster side. If PCM output does not change when commanded but cluster side does (or vice versa), narrow fault to harness/connector between them.
- Check continuity and resistance of the MIL circuit between PCM and cluster. Repair any open/ high-resistance sections (repair wiring, replace connectors or pigtails as needed).
- If wiring and lamp check good, inspect/bench-test instrument cluster lamp/LED circuitry or substitute a known-good cluster to verify.
- Only consider replacement of the PCM/ECM after fully diagnosing and verifying that the PCM MIL driver is faulty and all wiring/cluster options have been ruled out.
- After repair, clear codes, perform KOEO MIL check and use scan tool to command MIL ON/OFF; road test and re-scan to confirm code does not return.
Likely causes
- Open/disconnected MIL lamp connector or broken wire between PCM and cluster
- Failed MIL lamp (bulb or LED) or failed instrument cluster circuit
- Blown fuse protecting MIL/cluster circuit
- PCM/ECM MIL output driver failed (less common)
Fault status
Similar codes
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HTML ManualP0650
CAN-Bus No Communication with CIM (Steering Column Module)
Causes
- Blown fuse or fusible link for instrument cluster/PCM power
- Open or damaged wiring between PCM and instrument cluster (broken conductor, chafe, connector corrosion)
- Faulty instrument cluster MIL bulb or LED assembly
- Poor or missing ground at instrument cluster or PCM
- Faulty PCM/ECM MIL driver transistor or internal open circuit
- Aftermarket equipment or harness modification interrupting the MIL circuit
Symptoms
- Check Engine Light (MIL) does not illuminate during key ON bulb check
- MIL remains off when a monitored fault is present
- MIL may be intermittent or only illuminate under vibration/wiring movement
- No MIL illumination during scan-tool commanded lamp ON test
What to check
- Read and record DTC(s) with a scan tool and note freeze-frame/live data
- Visual inspection of instrument cluster area, wiring harness, and connectors for damage or corrosion
- Verify instrument panel fuses and fusible links are present and good
- Perform key ON engine OFF (KOEO) MIL bulb check: MIL should illuminate for a few seconds
- Use scan tool to command MIL ON/OFF and observe response
- Backprobe and measure voltage/continuity at the MIL connector, PCM MIL output pin, and ground
Signal parameters
- Key ON (engine off) MIL lamp: lamp circuit should show battery voltage at lamp connector when lamp is OFF (~11–13.5 V depending on battery state)
- When MIL is commanded ON by PCM: the PCM typically pulls the lamp circuit to ground — measured voltage at PCM output should be low (near 0 V) when ON
- Continuity between PCM MIL output pin and instrument cluster MIL pin: low resistance expected (typically
- Open circuit reading is effectively infinite resistance or no continuity
- Connector terminal voltages: good ground
Diagnostic algorithm
- Connect a scan tool, record P0650 and any related codes; clear codes and see if P0650 returns.
- Verify MIL behavior: with key ON (engine off) confirm MIL lights for bulb-check seconds. If it does, the lamp and cluster circuit likely work — issue may be intermittent or PCM-side.
- Check fuses and fusible links for instrument cluster and PCM power/ignition circuits; replace any blown fuses and retest.
- Perform a visual inspection of harness and connectors from PCM to instrument cluster — look for pin corrosion, bent/ pushed-out terminals, chafing, or previous repairs.
- Use a multimeter to backprobe the MIL lamp connector at the cluster: measure for battery voltage with lamp OFF and low resistance to ground when the scanner commands MIL ON. Record voltages.
- Backprobe the PCM MIL output pin and compare to cluster side. If PCM output does not change when commanded but cluster side does (or vice versa), narrow fault to harness/connector between them.
- Check continuity and resistance of the MIL circuit between PCM and cluster. Repair any open/ high-resistance sections (repair wiring, replace connectors or pigtails as needed).
- If wiring and lamp check good, inspect/bench-test instrument cluster lamp/LED circuitry or substitute a known-good cluster to verify.
- Only consider replacement of the PCM/ECM after fully diagnosing and verifying that the PCM MIL driver is faulty and all wiring/cluster options have been ruled out.
- After repair, clear codes, perform KOEO MIL check and use scan tool to command MIL ON/OFF; road test and re-scan to confirm code does not return.
Likely causes
- Open/disconnected MIL lamp connector or broken wire between PCM and cluster
- Failed MIL lamp (bulb or LED) or failed instrument cluster circuit
- Blown fuse protecting MIL/cluster circuit
- PCM/ECM MIL output driver failed (less common)
