Probable Causes:

• A/C Switch or Switch Circuit
• A/C Amplifier
• Accelerator Pedal or Cable
• ECU
• Neutral/Start Switch or Switch Circuit
• Throttle Position Sensor or Sensor Circuit

To check throttle position sensor or circuit, see Code 41.

To check A/C switch signal, use the following procedure.

Fig 1: Code 51/Test No. 9 Schematic Switch Signal

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Fig 2: Code 51/Test No. 9 Flow Chart Switch Signal

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