P0953: ASM Control Circuit High

Definition

The OBD2 code P0953 indicates a high voltage condition in the Automatic Shift Management (ASM) control circuit, which may suggest a malfunction in the transmission control system

Common causes

Faulty ASM control module
Damaged wiring or connectors
Short circuit in the ASM control circuit
Open circuit in the ASM control circuit
Corroded connectors
Faulty sensors related to ASM
Poor ground connection

Common misdiagnoses

Transmission control module failure
Faulty wiring or connectors
Defective transmission solenoid
Incorrectly diagnosed transmission fluid issues
Engine control module (ECM) problems
Misinterpretation of related codes
Faulty sensors unrelated to ASM control
Mechanical transmission issues

Troubleshooting steps

1. Check for Additional Codes

Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide more context and help identify related issues
2. Inspect Wiring and Connectors
3. Visually inspect the wiring and connectors associated with the ASM control circuit. Look for signs of damage, corrosion, or loose connections
4. Pay special attention to any frayed wires or broken connectors that could cause a short circuit or high resistance
5. Test the Voltage
6. Use a multimeter to measure the voltage at the ASM control circuit. Compare the readings to the specifications in the vehicle’s service manual
7. If the voltage is higher than expected, there may be a short circuit or a problem with the control module
8. Check the ASM Control Module
9. If the wiring and connectors are in good condition, the issue may lie with the ASM control module itself
10. Test the module according to the manufacturer’s specifications. This may involve checking for proper operation and ensuring it is receiving the correct input signals
11. Inspect Related Components
12. Check other components that may interact with the ASM system, such as the transmission control module (TCM), sensors, and actuators
13. Ensure that all related components are functioning correctly and are not causing interference
14. Clear Codes and Test Drive
15. After performing inspections and repairs, clear the trouble codes using the OBD-II scanner
16. Take the vehicle for a test drive to see if the code reappears. Monitor the vehicle’s performance during the drive
17. Consult Technical Service Bulletins (TSBs)
18. Check for any TSBs related to the P0953 code for your specific vehicle make and model. Manufacturers may have issued guidance or fixes for known issues
19. Seek Professional Help
20. If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who has experience with transmission systems and OBD-II diagnostics. By following these steps, you can systematically diagnose and address the issue related to the P0953 code

Definition

Common causes

Common misdiagnoses

Troubleshooting steps

1. Check for Additional Codes

2. Inspect Wiring and Connectors

3. Visually inspect the wiring and connectors associated with the ASM control circuit. Look for signs of damage, corrosion, or loose connections

4. Pay special attention to any frayed wires or broken connectors that could cause a short circuit or high resistance

5. Test the Voltage

6. Use a multimeter to measure the voltage at the ASM control circuit. Compare the readings to the specifications in the vehicle’s service manual

7. If the voltage is higher than expected, there may be a short circuit or a problem with the control module

8. Check the ASM Control Module

9. If the wiring and connectors are in good condition, the issue may lie with the ASM control module itself

10. Test the module according to the manufacturer’s specifications. This may involve checking for proper operation and ensuring it is receiving the correct input signals

11. Inspect Related Components

12. Check other components that may interact with the ASM system, such as the transmission control module (TCM), sensors, and actuators

13. Ensure that all related components are functioning correctly and are not causing interference

14. Clear Codes and Test Drive

15. After performing inspections and repairs, clear the trouble codes using the OBD-II scanner

16. Take the vehicle for a test drive to see if the code reappears. Monitor the vehicle’s performance during the drive

17. Consult Technical Service Bulletins (TSBs)

18. Check for any TSBs related to the P0953 code for your specific vehicle make and model. Manufacturers may have issued guidance or fixes for known issues

19. Seek Professional Help

20. If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who has experience with transmission systems and OBD-II diagnostics. By following these steps, you can systematically diagnose and address the issue related to the P0953 code