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Pinpoint Test G: DTCs B2844 and U2472




Steering Column Switches

Pinpoint Test G: DTCs B2844 and U2472

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

Normal Operation

The Smart Junction Box (SJB) contains several inputs that monitor the voltage outputs from the ignition switch. The SJB (Smart Junction Box) uses these inputs to determine the ignition switch position and then sends that information to various modules over the High Speed Controller Area Network (HS-CAN) bus. The ignition switch is designed so that only one output (ACC, RUN or START) is sent to the SJB (Smart Junction Box) at a time.

- DTC B2844 (Ignition Fault)- If the SJB (Smart Junction Box) receives an invalid ignition RUN input or cannot receive the ignition RUN input during normal operation, DTC B2844 is set.

- DTC U2472 (Unexpected Ignition State)- If the SJB (Smart Junction Box) does not receive the ignition RUN signal or receives conflicting ignition switch signals while performing an on-demand self test, DTC U2472 is set.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Ignition switch

- SJB (Smart Junction Box)

PINPOINT TEST G : DTCs B2844 AND U2472

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

NOTE: Verify that battery voltage is 10 volts or greater.

G1 CHECK THE SJB (Smart Junction Box) DTCs

- Use the recorded SJB (Smart Junction Box) DTCs from the continuous and on-demand self tests.

Is DTC B2A20 present?

Yes
GO to Pinpoint Test F. Pinpoint Test F: DTC B2A20

No
GO to G2.

G2 CHECK THE IGNITION SWITCH PIDs

- Connect the scan tool.

- Ignition ON.

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

- Monitor the following ignition switch PIDs while cycling the ignition switch through each position:
- ECU Derived Ignition State-OFF (IGN_O_ECU)
- ECU Derived Ignition State-ACC (IGN_A_ECU)
- ECU Derived Ignition State-RUN (IGN_R_ECU)
- ECU Derived Ignition State-START (IGN_S_ECU)


Does each PID display YES when the ignition switch is moved into the corresponding position and NO when the switch is moved to another position?

Yes
The condition is not present at this time. INSPECT SJB (Smart Junction Box) connectors C2280A and C2280B for corrosion, spread terminals and/or pushed-out pins. REPAIR as necessary. CLEAR the DTCs. REPEAT the self-test.

No
If IGN_A_ECU is displayed YES at all times, Non-Hybrid:GO to G3. Hybrid:GO to G4.

If IGN_R_ECU is displayed YES at all times, GO to G6.

If IGN_S_ECU displayed YES at all times, GO to Pinpoint Test F. Pinpoint Test F: DTC B2A20

If IGN_O_ECU displayed YES at all times, GO to Pinpoint Test A. Pinpoint Test A: No Power in All Ignition Switch Positions

If IGN_A_ECU displayed NO at all times, GO to Pinpoint Test B. Pinpoint Test B: No Power in ACC

If IGN_R_ECU displayed NO at all times, GO to Pinpoint Test C. Pinpoint Test C: No Power in RUN

If IGN_S_ECU displayed NO at all times, Non-Hybrid:GO to Pinpoint Test D. Pinpoint Test D: No Power in START Hybrid:GO to Pinpoint Test E.

G3 CHECK SJB (Smart Junction Box) FUSE 43 (10A) OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) Fuse 43 (10A).

- Ignition ON.

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

- Monitor the ignition switch ACC position PID IGN_A_ECU while cycling the ignition switch through each position.

Does the PID display YES when the ignition switch is moved through all switch positions?

Yes
GO to G4.

No
REPAIR circuit CBP43 (GY). CLEAR the DTCs. REPEAT the self-test.

G4 CHECK SJB (Smart Junction Box) FUSE 45 (5A) OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) Fuse 45 (5A).

- Ignition ON.

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

- Monitor the ignition switch ACC position PID IGN_A_ECU while cycling the ignition switch through each position.

Does the PID display YES when the ignition switch is moved through all switch positions?

Yes
GO to G5.

No
REPAIR circuit CBP45 (YE). CLEAR the DTCs. REPEAT the self-test.

G5 CHECK THE IGNITION SWITCH

- Ignition OFF.

- Disconnect: Ignition Switch C250.

- Carry out the Ignition Switch component test. Component Tests and General Diagnostics

Did the ignition switch pass the component test?

Yes
REPAIR circuit CDC33 (VT/GN). CLEAR the DTCs. REPEAT the self-test.

No
INSTALL a new ignition switch. REFER to Ignition Switch . TEST the system for normal operation. CLEAR the DTCs. REPEAT the self-test.

G6 CHECK SJB (Smart Junction Box) FUSE 44 (10A) OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) Fuse 44 (10A).

- Ignition ON.

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

- Monitor the ignition switch RUN position PID IGN_R_ECU while cycling the ignition switch through each position.

Does the PID display YES when the ignition switch is moved through all switch positions?

Yes
GO to G7.

No
REPAIR circuit CBP44 (VT). CLEAR the DTCs. REPEAT the self-test.

G7 CHECK SJB (Smart Junction Box) FUSE 42 (10A) OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) Fuse 42 (10A).

- Ignition ON.

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

- Monitor the ignition switch RUN position PID IGN_R_ECU while cycling the ignition switch through each position.

Does the PID display YES when the ignition switch is moved through all switch positions?

Yes
GO to G8.

No
REPAIR circuit CBP42 (GN). CLEAR the DTCs. REPEAT the self-test.

G8 CHECK SJB (Smart Junction Box) FUSE 29 (5A) OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) Fuse 29 (5A).

- Ignition ON.

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

- Monitor the ignition switch RUN position PID IGN_R_ECU while cycling the ignition switch through each position.

Does the PID display YES when the ignition switch is moved through all switch positions?

Yes
GO to G9.

No
REPAIR circuit CBP29 (WH/VT). CLEAR the DTCs. REPEAT the self-test.

G9 CHECK SJB (Smart Junction Box) FUSE 46 (7.5A) OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) Fuse 46 (7.5A).

- Ignition ON.

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

- Monitor the ignition switch RUN position PID IGN_R_ECU while cycling the ignition switch through each position.

Does the PID display YES when the ignition switch is moved through all switch positions?

Yes
GO to G10.

No
REPAIR circuit CBP46 (WH/BU). CLEAR the DTCs. REPEAT the self-test.

G10 CHECK SJB (Smart Junction Box) FUSE 36 (5A) OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) Fuse 36 (5A).

- Ignition ON.

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

- Monitor the ignition switch RUN position PID IGN_R_ECU while cycling the ignition switch through each position.

Does the PID display YES when the ignition switch is moved through all switch positions?

Yes
GO to G11.

No
REPAIR circuit CBP36 (BU/BN). CLEAR the DTCs. REPEAT the self-test.

G11 CHECK SJB (Smart Junction Box) FUSE 35 (10A) OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) Fuse 35 (10A).

- Ignition ON.

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

- Monitor the ignition switch RUN position PID IGN_R_ECU while cycling the ignition switch through each position.

Does the PID display YES when the ignition switch is moved through all switch positions?

Yes
GO to G12.

No
REPAIR circuit CBP35 (YE/GY). CLEAR the DTCs. REPEAT the self-test.

G12 CHECK SJB (Smart Junction Box) FUSE 32 (10A) OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) Fuse 32 (10A).

- Ignition ON.

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

- Monitor the ignition switch RUN position PID IGN_R_ECU while cycling the ignition switch through each position.

Does the PID display YES when the ignition switch is moved through all switch positions?

Yes
For hybrid vehicles,GO to G13.

For non-hybrid vehicles,GO to G14.

No
REPAIR circuit CBP32 (GN/VT). CLEAR the DTCs. REPEAT the self-test.

G13 CHECK SJB (Smart Junction Box) FUSE 37 (10A) OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) Fuse 37 (10A) (if equipped).

- Ignition ON.

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

- Monitor the ignition switch RUN position PID IGN_R_ECU while cycling the ignition switch through each position.

Does the PID display YES when the ignition switch is moved through all switch positions?

Yes
GO to G14.

No
REPAIR circuit SBP37 (WH). CLEAR the DTCs. REPEAT the self-test.

G14 CHECK THE IGNITION SWITCH RUN OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: SJB (Smart Junction Box) C2280B.

- Disconnect: SJB (Smart Junction Box) C2280E.

- Ignition ON.

- Measure the voltage between SJB (Smart Junction Box) C2280E-1, circuit CDC34 (WH/OG), harness side and ground while moving the ignition switch through all switch positions.





Is voltage present when the ignition switch is moved through all switch positions?

Yes
GO to G15.

No
GO to G16.

G15 CHECK THE IGNITION SWITCH

- Ignition OFF.

- Disconnect: Ignition Switch C250.

- Carry out the Ignition Switch component test. Component Tests and General Diagnostics

Did the ignition switch pass the component test?

Yes
REPAIR circuit CDC34 (WH/OG). CLEAR the DTCs. REPEAT the self-test.

No
INSTALL a new ignition switch. REFER to Ignition Switch . CLEAR the DTCs. REPEAT the self-test.

G16 CHECK FOR CORRECT SJB (Smart Junction Box) OPERATION

- Ignition OFF.

- Disconnect: All SJB (Smart Junction Box) connectors.

- Check the SJB (Smart Junction Box) connectors for:
- corrosion.
- pushed-out pins.
- spread terminals.


- Connect: All SJB (Smart Junction Box) connectors making sure that they are seated correctly.

- Make sure the connectors are seated correctly, then operate the system and verify the concern is still present.

Is the concern still present?

Yes
INSTALL a new SJB (Smart Junction Box). CLEAR the DTC. REPEAT the self-test.

No
The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.

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