DTC B270A
Diagnostic Instructions
DTC Descriptors
DTC B270A 01: Park Lock Solenoid Control
Circuit Short to Battery |
DTC B270A 02: Park Lock Solenoid Control
Circuit Short to Ground |
DTC B270A 04: Park Lock Solenoid Control
Circuit Open |
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Control
|
B270A 02
|
B270A 04
|
B270A 01
|
-
|
Ground
|
-
|
B270A 04
|
-
|
-
|
|
|
Circuit/System Description
The body control module (BCM) controls the transmission shift
lock control solenoid actuator by providing a battery positive
voltage to the solenoid when the brake pedal is applied. The BCM
monitors the voltage and current flow of the control circuit.
Conditions for Running the DTC
• |
The ignition switch is in the
ON position. |
• |
The brake pedal is
applied. |
• |
The transmission is in the
PARK position. |
• |
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 or short to voltage 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 transmission shift lock control solenoid
actuator until the next key cycle.
Conditions for Clearing the DTC
• |
A current DTC B270A will clear
when the malfunction is no longer present and the ignition switch
is cycled. |
• |
A history DTC will clear after
100 ignition cycles with no current DTC active during the 100
ignition cycles. |
Reference Information
Schematic Reference
Shift Lock Control Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Automatic Transmission Shift Lock Control Description and
Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
2. |
Verify the scan tool Brake
Transmission Shift Interlock Solenoid Actuator Command parameter
changes from Inactive to Active when the brake pedal is
applied. |
⇒ If the Brake
Transmission Shift Interlock Solenoid Actuator Command does not
change
Refer to
Stop Lamps Malfunction ⇓
If the Brake Transmission Shift Interlock Solenoid
Actuator Command changes
3. |
Verify the S3 transmission
shift lever moves out of the PARK position when the brake pedal is
applied. |
⇒ If the the S3
transmission shift lever does not move out of the PARK
position
Refer to Circuit/System Testing.
⇓ If the the S3
transmission shift lever does move out of the PARK
position All OK.
Circuit/System Testing
1. |
Ignition 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 Ω
between the ground circuit terminal 2 and ground. |
⇒ If 10 Ω or
greater
|
2.2 |
Test for less than 2 Ω
in the ground circuit end to end. |
⇒ |
If 2 Ω or greater, repair the open/high resistance in the
circuit. |
⇒ |
If less than 2 Ω, repair the open/high resistance in the
ground connection. |
⇓ If less than 10
Ω
3. |
Ignition ON, 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
|
4.1 |
Ignition OFF, disconnect the
harness connector at the K9 body control module. |
|
4.2 |
Test for infinite resistance
between the control circuit and ground. |
⇒ |
If less than infinite resistance, repair the short to ground on
the circuit. |
|
4.3 |
Test for less than 2 Ω
in the control circuit end to end. |
⇒ |
If 2 Ω or greater, repair the open/high resistance in the
circuit. |
|
4.5 |
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
|
4.1 |
Ignition OFF, disconnect the
harness connector at the K9 body control module, ignition
ON. |
|
4.2 |
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.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the repair.
|