Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Inspection Procedure
- INSPECT TRANSMISSION CONTROL SWITCH
- Disconnect the L42 transmission control switch connector.
- Measure the resistance between each terminal of the transmission control switch when the shift lever is moved to each position.
Standard Resistance
RESISTANCE REFERENCETester Connection Condition Specified Condition 3 (IG) - 7 (S) Shift lever on S, "+" or Below 1 Ω 2 (SFTU) - 5 (E) Shift lever held in "+" (Up-shift) Below 1 Ω 1 (SFTD) - 5 (E) Shift lever held in "-" (Down-shift) Below 1 Ω 3 (IG) - 7 (S) Shift lever not on S, "+" or "-" 10 kΩ or higher 2 (SFTU) - 5 (E) Shift lever on S 10 kΩ or higher 1 (SFTD) - 5 (E) Shift lever on S 10 kΩ or higher
NG: REPLACE TRANSMISSION FLOOR SHIFT ASSEMBLY (TRANSMISSION CONTROL SWITCH) (See REMOVAL )
OK: Go to next step
- CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - BATTERY, BODY GROUND)
- Disconnect the L42 transmission control switch connector.
- Turn the engine switch on (IG).
- Measure the voltage of the wire harness side connector.
Standard Voltage
VOLTAGE SPECIFICATIONTester Connection Switch Condition Specified Condition L42-3 (IG) - Body ground Engine switch on (IG) 11 to 14 V L42-3 (IG) - Body ground Engine switch off Below 1 V - Turn the engine switch off.
- Measure the resistance of the wire harness side connector.
Standard Resistance
RESISTANCE REFERENCETester Connection Condition Specified Condition L42-5 (E) - Body ground Always Below 1 Ω
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go to next step
- CHECK HARNESS AND CONNECTOR (TRANSMISSION CONTROL SWITCH - ECM)
- Turn the engine switch on (IG).
- Measure the voltage of the wire harness side connector.
Standard Voltage
VOLTAGE SPECIFICATIONTester Connection Condition Specified Condition A13-16 (S) - Body ground - Engine switch on (IG)
- Shift lever on S, "+" or "-"
11 to 14 V A13-16 (S) - Body ground - Engine switch on (IG)
- Shift lever not on S, "+" or "-"
Below 1 V - Turn the engine switch off.
- Disconnect the A13 ECM connector.
- Measure the resistance of the wire harness side connector.
Standard Resistance
RESISTANCE REFERENCETester Connection Condition Specified Condition A13-8 (SFTU) - Body ground Shift lever held In "+" (Up-shift) Below 1 Ω A13-7 (SFTD) - Body ground Shift lever held In "-" (Down-shift) Below 1 Ω A13-8 (SFTU) - Body ground Shift lever on S 10 kΩ or higher A13-7 (SFTD) - Body ground Shift lever on S 10 kΩ or higher
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (See PROBLEM SYMPTOMS TABLE )
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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