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B2A20




Steering Column Switches

Pinpoint Test E: DTC B2A20

Refer to Wiring Diagram Set 13, Power Distribution/SJB for schematic and connector information [1][2]Diagrams By Number.

Normal Operation

The ignition switch is spring loaded to automatically return to the RUN position after being placed in the START position. A microprocessor in the Smart Junction Box (SJB) monitors the voltage output from the ignition switch while the switch is in the START position.

- DTC B2A20 (Ignition Stuck in START)- If the SJB (Smart Junction Box) receives a start signal for more than 30 seconds, DTC (Diagnostic Trouble Code) B2A20 will be set.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Ignition switch

- ACM (Audio Front Control Module)

- PCM

- SJB (Smart Junction Box)

- Starter relay

PINPOINT TEST E : DTC B2A20

NOTICE: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.

E1 CHECK THE IGNITION SWITCH

- Ignition OFF.

- Disconnect: Ignition Switch C250.

- Carry out the Ignition Switch- Mechanical Component Test. Component Tests and General Diagnostics

Does the switch pass the test?

Yes
GO to E2.

No
INSTALL a new ignition switch. REFER to Ignition Switch . CLEAR the DTC. TEST the system for normal operation.

E2 CHECK THE ELECTRICAL FUNCTION OF THE IGNITION SWITCH

- Carry out the ignition Switch Component Test.

Does the switch pass the test?

Yes
GO to E3.

No
INSTALL a new ignition switch. REFER to Ignition Switch . CLEAR the DTC. TEST the system for normal operation.

E3 CHECK THE SJB (Smart Junction Box) PID

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: DataLogger- SJB (Smart Junction Box).

- Monitor the IGN_S_ECU PID.

Does the PID display No?

Yes
GO to E11.

No
GO to E4.

E4 ISOLATE THE ACM (Audio Front Control Module)

- Ignition OFF.

- Disconnect: Audio Control Module ACM (Audio Front Control Module) C290D.

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: DataLogger- SJB (Smart Junction Box).

- Monitor the IGN_S_ECU PID.

Does the PID display No?

Yes
GO to E9.

No
GO to E5.

E5 CHECK THE START CIRCUIT TO THE ACM (Audio Front Control Module) FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) C2280B.

- Ignition ON.

- Measure the voltage between ground and SJB (Smart Junction Box) C2280B-2 harness side.





Is any voltage present?

Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

No
GO to E6

E6 ISOLATE THE START RELAY CONTROL CIRCUIT

- Ignition OFF.

- Disconnect: Start Relay.

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: DataLogger- SJB (Smart Junction Box).

- Monitor the IGN_S_ECU PID.

Does the PID display No?

Yes
INSTALL a new relay. TEST the system for normal operation.

No
GO to E7.

E7 CHECK THE IGNITION START CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: PCM (Powertrain Control Module) C1381B OR C175B.

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: DataLogger- SJB (Smart Junction Box).

- Monitor the IGN_S_ECU PID.

Does the PID display No?

Yes
GO to E10.

No
GO to E8.

E8 CHECK THE START CIRCUIT TO THE PCM (Powertrain Control Module) FOR A SHORT TO VOLTAGE

- Measure the voltage between ground and SJB (Smart Junction Box) C2280E-2 harness side.





Is any voltage present?

Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

No
GO to E11.

E9 CHECK THE AUDIO CONTROL MODULE (ACM) FOR CORRECT OPERATION

- Ignition OFF.

- Disconnect all Audio Control Module (ACM) connectors.

- Check the connectors for:
- corrosion.
- pushed-out pins.
- spread terminal.


- Repair any concern found.
Refer to Wiring Diagram Set 5 for schematic and connector information [1][2]Diagrams By Number.

- Reconnect all Audio Control Module (ACM) connectors.

- Make sure the connectors are seated and latched correctly.

- Reconnect all previously disconnected, fuse(s), relay(s) and connector(s).

- Make sure they are seated and latch correctly.

- Operate the system and determine if the concern is still present.

Is the concern still present?

Yes
INSTALL a new ACM (Audio Front Control Module). REPEAT the self-test, then TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

E10 CHECK THE PCM (Powertrain Control Module) FOR CORRECT OPERATION

- Ignition OFF.

- Disconnect all PCM (Powertrain Control Module) connectors

- Check the connectors for:
- corrosion.
- pushed-out pins.
- spread terminal.


- Repair any concern found.
Refer to Wiring Diagram Set 5 for schematic and connector information [1][2]Diagrams By Number.

- Reconnect all PCM (Powertrain Control Module) connectors.

- Make sure the connectors are seated and latched correctly.

- Reconnect all previously disconnected, fuse(s), relay(s) and connector(s).

- Make sure they are seated and latched correctly.

- Operate the system and determine if the concern is still present.

Is the concern still present?

Yes
INSTALL a new PCM (Powertrain Control Module). CLEAR the DTCs. REPEAT the self-test, then TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

E11 CHECK THE SJB (Smart Junction Box) FOR CORRECT OPERATION

- Ignition OFF.

- Disconnect all SJB (Smart Junction Box) connectors.

- Check the connectors for:
- corrosion.
- pushed-out pins.
- spread terminal.


- Repair any concern found.
Refer to Wiring Diagram Set 5 for schematic and connector information [1][2]Diagrams By Number.

- Reconnect all SJB (Smart Junction Box) connectors.

- Make sure the connectors are seated and latched correctly.

- Reconnect all previously disconnected, fuse(s), relay(s) and connector(s).

- Make sure they are seated and latch correctly.

- Operate the system and determine if the concern is still present.

Is the concern still present?

Yes
INSTALL a new SJB (Smart Junction Box). REPEAT the self-test, then TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

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