Shift Lock Control System: Diagnosis Chevrolet Volt I

Diagnostic Code Index

DIAGNOSTIC CODE INDEX

Diagnostic Instructions

1. Perform the «Diagnostic System Check - Vehicle»(ref-487438-S13406627192012072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-487438-S08433352102012072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-487438-S20414004952012072300000) provides an overview of each diagnostic category.

Diagnostic Fault Information

Conditions for Running the DTC

1. The ignition switch is in the ON position.
2. The brake pedal is applied.
3. The transmission is in the PARK position.
4. The DTC runs continuously once the above conditions are met.

Conditions for Setting the DTC

B270A 01

The body control module detects a short to voltage in the transmission shift lock control solenoid actuator control circuit for 1 second.

B270A 02

The body control module detects a short to ground in the transmission shift lock control solenoid actuator control circuit for 1 second.

B270A 04

The body control module detects an open in the transmission shift lock control solenoid actuator control circuit for 1 second.

Action Taken When the DTC Sets

The body control module will not attempt to enable the voltage supply circuit of the automatic transmission park lock control solenoid until the next power switch cycle.

Conditions for Clearing the DTC

1. A current DTC B270A will clear when the malfunction is no longer present and the power switch is cycled.
2. A history DTC will clear after 100 ignition cycles with no current DTC active during the 100 power switch cycles.

Circuit/System Testing

1. Vehicle OFF and all vehicle systems OFF, disconnect the harness connector at the S3 transmission shift lever. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 2 and ground. If 10 ohms or greater Vehicle OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Vehicle in Service Mode, connect a test lamp between the control circuit terminal 4 and the ground circuit terminal 2.
4. Verify the test lamp turns ON and OFF when commanding the Brake Transmission Shift Interlock Solenoid Actuator ON and OFF with a scan tool. If the test lamp is always OFF Vehicle OFF, disconnect the harness connector at the K9 body control module. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms Vehicle in Service Mode. Verify a test lamp illuminates between each B+ and ignition circuit terminal at the control module harness connector. If the test lamp does not illuminate, repair the circuit or fuse as necessary. If the test lamp illuminates at each B+ and ignition circuit, replace the K9 body control module. If the test lamp is always ON Vehicle OFF, disconnect the harness connector at the K9 body control module, Vehicle in Service Mode. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K9 body control module. If the test lamp turns ON and OFF
5. Test or replace the S3 transmission shift lever.

Component Testing

Dynamic Test

1. Install a 10 A fused jumper wire between the control terminal 4 and 12 V. Momentarily install a jumper wire between the ground terminal 2 and ground.
2. Verify the solenoid turns on & off/clicks, etc. If the solenoid does not turn on & off/clicks, etc. Replace the S3 transmission shift lever. If the solenoid does turn on & off/clicks, etc.
3. All OK

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the automatic transmission shift lock control. Refer to «Checking Aftermarket Accessories»(ref-487461-S39907746842012072300000) .
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Symptom List

Refer to a symptom diagnostic procedure in order to diagnose the symptom

Transmission Control Lever Malfunction

1. Perform the «Diagnostic System Check - Vehicle»(ref-487438-S13406627192012072300000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-487438-S08433352102012072300000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-487438-S20414004952012072300000) provides an overview of each diagnostic category.

1. Vehicle OFF and all vehicle systems OFF, disconnect the harness connector at the S3 transmission shift lever. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 2 and ground. If 10 ohms or greater Vehicle OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Vehicle in Service Mode, connect a test lamp between the control circuit terminal 4 and the ground circuit terminal 2.
4. Verify the test lamp turns ON and OFF when commanding the Brake Transmission Shift Interlock Solenoid Actuator ON and OFF with a scan tool. If the test lamp is always OFF Vehicle OFF, disconnect the harness connector at the K9 body control module. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms Vehicle in Service Mode. Verify a test lamp illuminates between each B+ and ignition circuit terminal at the control module harness connector. If the test lamp does not illuminate, repair the circuit or fuse as necessary. If the test lamp illuminates at each B+ and ignition circuit, replace the K9 body control module. If the test lamp is always ON Vehicle OFF, disconnect the harness connector at the K9 body control module, Vehicle in Service Mode. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K9 body control module. If the test lamp turns ON and OFF
5. Test or replace the S3 transmission shift lever.

Dynamic Test

1. Install a 10 A fused jumper wire between the control terminal 4 and 12 V. Momentarily install a jumper wire between the ground terminal 2 and ground.
2. Verify the solenoid turns on & off/clicks, etc. If the solenoid does not turn on & off/clicks, etc. Replace the S3 transmission shift lever. If the solenoid does turn on & off/clicks, etc.
3. All OK