Pinpoint Test E: DTC B2A20
Steering Column Switches
Pinpoint Tests
Pinpoint Test E: DTC B2A20
Refer to Wiring Diagram Set 13, Power Distribution/SJB for schematic and connector information. 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. This microprocessor is also connected to a few additional components.
The PCM and the starter relay are connected to the SJB microprocessor along circuit CET40 (GN/OG). On vehicles equipped with a manual transmission, the PCM and relay are connected directly to the microprocessor. On vehicles with an automatic transmission, circuit CET40 (GN/OG) passes through the digital Transmission Range (TR) sensor before going to the PCM and relay.
The Audio Control Module (ACM) is connected to the microprocessor through SJB fuse 28 (5A) along CBP28 (GY/VT).
- DTC B2A20 (Ignition Stuck in START) - The SJB continuously monitors the ignition switch state, if the SJB receives a START signal for more than 30 seconds, DTC B2A20 will be set. A short to voltage on any of the circuits mentioned above will cause DTC B2A20 to set. The SJB does not monitor the start circuit during an on-demand self test.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Ignition switch
- ACM
- PCM
- SJB
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 MECHANICAL FUNCTION OF THE IGNITION SWITCH
- Carry out the Ignition Switch - Mechanical Component Test. Component Tests and General Diagnostics
- Does the switch pass the test?
Yes
GO to E2.
No
CARRY OUT the repair direction given in the component test. 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 Ignition Switch. CLEAR the DTC. TEST the system for normal operation.
-------------------------------------------------
E3 ISOLATE THE IGNITION SWITCH START CIRCUIT
- Disconnect: SJB Fuse 28 (5A).
- Disconnect: SJB C2280E.
- Connect the scan tool.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - SJB.
- Monitor the ECU Derived Ignition State-START (IGN_S_ECU) PID.
- Does the PID display No?
Yes
GO to E4.
No
REPAIR circuit CDC35 (BU/WH). CLEAR the DTC. TEST the system for normal operation.
-------------------------------------------------
E4 ISOLATE THE ACM AND THE ACM START CIRCUIT
- Connect: SJB Fuse 28 (5A).
- Enter the following diagnostic mode on the scan tool: DataLogger - SJB.
- Monitor the IGN_S_ECU PID.
- Does the PID display No?
Yes
For vehicles equipped with an automatic transmission, GO to E7.
For vehicles equipped with a manual transmission, GO to E8.
No
GO to E5.
-------------------------------------------------
E5 ISOLATE THE ACM
- Ignition OFF.
- Disconnect: ACM C290D.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - SJB.
- Monitor the IGN_S_ECU PID.
- Does the PID display No?
Yes
GO to E6.
No
REPAIR circuit CBP28 (GY/VT). CLEAR the DTC. TEST the system for normal operation.
-------------------------------------------------
E6 CHECK FOR CORRECT ACM OPERATION
- Ignition OFF.
- Check ACM C290D for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect: SJB C2280E.
- Connect: ACM C290D.
- Make sure the connectors seat correctly, then operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new ACM. REFER to Accessories and Optional Equipment. 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. CLEAR the DTC. TEST the system for normal operation.
-------------------------------------------------
E7 ISOLATE THE DIGITAL TR SENSOR START CIRCUIT
- Ignition OFF.
- Connect: SJB C2280E.
- Disconnect: Digital TR Sensor C167.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - SJB.
- Monitor the IGN_S_ECU PID.
- Does the PID display No?
Yes
GO to E8.
No
REPAIR circuit CDC35 (BU/WH). CLEAR the DTC. TEST the system for normal operation.
-------------------------------------------------
E8 ISOLATE THE PCM
- Ignition OFF.
- Connect: Digital TR Sensor C167.
- Disconnect: PCM C175B.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - SJB.
- Monitor the IGN_S_ECU PID.
- Does the PID display No?
Yes
GO to E10.
No
GO to E9.
-------------------------------------------------
E9 ISOLATE THE START RELAY CONTROL CIRCUIT
- Disconnect: Start Relay.
- Enter the following diagnostic mode on the scan tool: DataLogger - SJB.
- Monitor the IGN_S_ECU PID.
- Does the PID display No?
Yes
REPAIR circuit CDC12 (YE). CLEAR the DTC. TEST the system for normal operation.
No
REPAIR circuit CET40 (GN/OG). CLEAR the DTC. TEST the system for normal operation.
-------------------------------------------------
E10 CHECK FOR CORRECT PCM OPERATION
- Ignition OFF.
- Check PCM C175B for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect: Start Relay.
- Connect: PCM C175B.
- Make sure the connector seats correctly, then operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new PCM. REFER to Computers and Control Systems. 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. CLEAR the DTC. TEST the system for normal operation.
-------------------------------------------------