P0A3F
DTC P0A3F, P0A40, P0C52, P0C53, P0C5C, P0C5D, or P1B03
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P0A3F
- Drive Motor Position Sensor Circuit
DTC P0A40
- Drive Motor Position Sensor Performance
DTC P0C52
- Drive Motor Position Sensor Circuit 1 Low Voltage
DTC P0C53
- Drive Motor Position Sensor Circuit 1 High Voltage
DTC P0C5C
- Drive Motor Position Sensor Circuit 2 Low Voltage
DTC P0C5D
- Drive Motor Position Sensor Circuit 2 High Voltage
DTC P1B03
- Drive Motor Position Sensor Circuit Tracking Lost
Diagnostic Fault Information
Circuit/System Description
The generator control module also called the starter generator control module is comprised of the following three control modules; the hybrid powertrain control module, 14 volt power module and the drive motor control module. These three control modules are non serviceable and are part of the generator control module.
The generator control module monitors the angular position, speed and direction of the starter generator rotor based upon the signals of the resolver-type motor position sensor. The position sensor contains a drive coil, two driven coils, and an irregular shaped metallic rotor. The metallic rotor is mechanically attached to the shaft of the starter generator.
At ignition ON, an AC voltage, 10 kHz excitation signal is output to the drive coil. The drive coil excitation signal creates a magnetic field surrounding the two driven coils and the irregular shaped rotor. The generator control module then monitors the two driven coil circuits for a return signal. The position of the irregular metallic rotor causes the magnetically-induced return signals of the driven coils to vary in size and shape. A comparison of the two driven coils signals allows the generator control module to determine the exact position, speed and direction of the starter generator rotor. The position sensor is a non-serviceable part of the starter generator.
Conditions for Running the DTC
* Ignition voltage is greater than 9.5V.
* The drive motor control module and hybrid powertrain control module are awake.
Conditions for Setting the DTC
P0A3F
Sin or Cos signal is less than 2.3V.
P0A40
Sin or Cos signal is greater than 4V.
P0C52
Drive Motor Position Sensor Circuit 1 reference voltage is less than 0.5 V.
P0C53
Drive Motor Position Sensor Circuit 1 reference voltage is greater than 4.5 V.
P0C5C
Drive Motor Position Sensor Circuit 2 reference voltage is less than 0.5 V.
P0C5D
Drive Motor Position Sensor Circuit 2 reference voltage is greater than 4.5 V.
P1B03
The generator control module tracking error is greater than 5 degrees.
Action Taken When the DTC Sets
* DTCs P0A3F, P0A40, P0C52, P0C53, P0C5C, P0C5D, and P1B03 are Type B DTCs.
* Starter generator operation is disabled.
* Autostop operation is disabled.
* Autostart operation is disabled.
* 14 volt power module remains active until hybrid battery power is depleted, or 14 volt power module power limits are exceeded, after which the high voltage contactor's relay is opened.
Conditions for Clearing the DTC
DTCs P0A3F, P0A40, P0C52, P0C53, P0C5C, P0C5D, and P1B03 are Type B DTCs.
Diagnostic Aids
* The starter generator position sensor circuits operate at very low current. These circuits are susceptible to moisture intrusion, coolant contamination, corrosion, and terminal damage. Extreme care must be taken when removing the starter generator, probing terminals and manipulating harnesses. Poor terminal connections can result in intermittent operation.
* If the customer comments that the problem occurs only during moist environmental conditions: rain, snow, vehicle wash, etc., inspect the sensor wiring and seals for signs of water intrusion.
* The sensor and reference circuit loops are a twisted pair with each pair covered in a grounded foil shield.
* The shield circuits are grounded inside the drive motor control module. Improperly grounded shield circuits may cause inaccurate sensor signals.
Reference Information
Schematic Reference
Hybrid/EV Controls Schematics
Connector End View Reference
* Component Connector End Views Sunshade - Left
* Inline Harness Connector End Views X110
Description and Operation
* Starter Generator Description and Operation
* Generator Control Module Description and Operation
* Hybrid Modes of Operation Description
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Testing
Note: You must perform the Component Testing before proceeding with Circuit/System Testing.
1. Ignition OFF, disconnect the X1 harness connector at the A15 Starter Generator.
2. Ignition ON.
3. Test for 1.7-3.2 V between the signal circuit terminals listed below and ground:
* Signal (S1) circuit terminal 1
* Signal (S3) circuit terminal 5
* Signal (S2) circuit terminal 6
* Signal (S4) circuit terminal 2
• If less than 1.7 V
1. Vehicle OFF, disconnect the X1 harness connector at the K59 Starter Generator Control Module.
Note: The following test must be performed at the K59 Starter Generator Control Module end of the wiring harness.
2. Test for infinite resistance between the appropriate signal circuit and the ground circuit listed below:
* Signal (S1) circuit terminal 10 and ground circuit terminal 2
* Signal (S3) circuit terminal 11 and ground circuit terminal 2
* Signal (S2) circuit terminal 8 and ground circuit terminal 1
* Signal (S4) circuit terminal 9 and ground circuit terminal 1
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for infinite resistance between the signal circuit and chassis ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
4. Test for less than 2 ohms in the signal circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K59 Starter Generator Control Module.
• If greater than 3.2 V
1. Ignition OFF, disconnect the X1 harness connector at the K59 Starter Generator Control Module, Ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K59 Starter Generator Control Module.
• If between 1.7-3.2 V
4. Test for 6.5-8.5 V between the reference circuit terminals listed below and ground:
* Reference terminal 3
* Reference terminal 4
• If less than 6.5 V
1. Ignition OFF, disconnect the X1 harness connector at the K59 Starter Generator Control Module.
Note: The following test must be performed at the K59 Starter Generator Control Module end of the wiring harness.
2. Test for infinite resistance between the reference circuit and the following ground paths:
* Chassis ground
* Ground circuit terminal 13
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohms in the reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K59 Starter Generator Control Module.
• If greater than 8.5 V
1. Ignition OFF, disconnect the X1 harness connector at the K59 Starter Generator Control Module, Ignition ON.
2. Test for less than 1 V DC between the reference circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K59 Starter Generator Control Module.
• If between 6.5-8.5 V
5. Verify DTC P0A3F, P0A40, P0C52, P0C53, P0C5C, P0C5D, or P1B03 is not set.
• If any of the DTCs are set
1. Program the K59 Starter Generator Control Module.
2. Verify the DTC does not set.
• If the DTC sets, replace the K59 Starter Generator Control Module.
• If the DTC does not set
3. All OK.
• If none of the DTCs are set
6. All OK.
Component Testing
Note: If moist environmental conditions: rain, snow, vehicle wash, etc. are present please refer to the appropriate Diagnostic Aids section above before doing component tests.
1. Ignition OFF, disconnect the X1 harness connector at the A15 Starter Generator.
2. Test for 10-35 ohms between the reference terminal 3 and the reference terminal 4.
• If not within the specified range
Replace the A15 Starter Generator.
• If within the specified range
3. Test for 30-60 ohms between the signal (S1) terminal 1 and the signal (S3) terminal 5.
• If not within the specified range
Replace the A15 Starter Generator.
• If within the specified range
4. Test for 30-60 ohms between the signal (S4) terminal 2 and the signal (S2) terminal 6.
• If not within the specified range
Replace the A15 Starter Generator.
• If within the specified range
5. Test for greater than 10,000 ohms between the terminals listed below and A15 Starter Generator case:
* Signal (S1) terminal 1
* Signal (S4) terminal 2
* Reference terminal 3
* Reference terminal 4
* Signal (S3) terminal 5
* Signal (S2) terminal 6
• If less than 10,000 ohms
Replace the A15 Starter Generator.
• If 10,000 ohms or greater
6. Test for infinite resistance between the terminals listed below:
* Terminals 1 and 3
* Terminals 1 and 2
* Terminals 2 and 3
• If less than infinite resistance
Replace the A15 Starter Generator.
• If infinite resistance
7. Refer to Circuit/System Testing.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Starter Generator Replacement
* Control Module References Control Module References for K59 Starter Generator Control Module, often referred to as Generator Control Module, replacement, programming and setup