P1742 – Subaru OBD-II 1996 & Newer models DTC

Subaru OBD-II 1996 & Newer models DTC P1742 – Auto Trans Diagnosis Input Signal Malfunction

DTC P1742 meaning on Subaru OBD-II 1996 & Newer models

DTC P1742 indicates an Auto Trans Diagnosis Input Signal Malfunction on Subaru vehicles equipped with OBD-II systems from 1996 onwards.

Subaru OBD-II 1996 & Newer models DTC P1742 symptoms

• Check Engine Light (MIL) illuminated
• Transmission shifting issues
• Reduced fuel efficiency

Subaru OBD-II 1996 & Newer models DTC P1742 causes

• Defective transmission control module (TCM)
• Wiring or connector issues in the transmission control circuit
• Faulty transmission speed sensor

Subaru OBD-II 1996 & Newer models DTC P1742 seriousness

The seriousness of DTC P1742 lies in the potential transmission operation problems it can cause. Ignoring this code may lead to further damage to the transmission system.

How to diagnose DTC P1742 on Subaru OBD-II 1996 & Newer models

1. Use an OBD-II scanner to retrieve the specific fault codes stored in the vehicle’s computer.
2. Inspect the transmission control module (TCM) for any visible damage or signs of malfunction.
3. Check the wiring and connectors in the transmission control circuit for loose connections or corrosion.
4. Test the transmission speed sensor for proper operation.

How to fix DTC P1742 on Subaru OBD-II 1996 & Newer models

1. Replace the faulty transmission control module (TCM) if diagnosed as the cause.
2. Repair or replace any damaged wiring or connectors in the transmission control circuit.
3. Replace the transmission speed sensor if found to be defective.
4. Clear the fault codes using the OBD-II scanner after completing repairs.

How to erase DTC P1742 on Subaru OBD-II 1996 & Newer models

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Follow the scanner’s instructions to access the DTC menu.
3. Select the option to clear the fault codes stored in the system.
4. Confirm the action and wait for the scanner to erase the DTC P1742 code.

Recommended tools for Subaru OBD-II 1996 & Newer models diagnostics

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Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

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