Probable Causes

To check throttle position sensor signal, see Code 41.

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

CODE 51/TEST NO. 11-SWITCH SIGNAL TROUBLE (3S-GTE)

Terminal	Trouble	Condition	STD Voltage
AC1-E1	No Voltage	Air Conditioning ON	8-14V

CODE 51/TEST NO. 11-SWITCH SIGNAL TROUBLE (4A-FE & 5S-FE)

Terminal	Trouble	Condition	STD Voltage
A/C-E1	No Voltage	Air Conditioning ON	8-14V

Fig 1: Code 51/Test No. 11 Schematic (4A-FE & 5S-FE) Switch Signal

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Fig 2: Code 51/Test No. 11 Flow Chart (4A-FE & 5S-FE) Switch Signal

Fig 3: Code 51/Test No. 11 Schematic (3S-GTE) Switch Signal

Fig 4: Code 51/Test No. 11 Flow Chart (3S-GTE) Switch Signal