Inspection Procedure

WARNING: This page is about a different car, the 2004 Lexus ES 330. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT STOP LAMP SWITCH OPERATION
1. Check that the stop lamp comes on while depressing the brake pedal, and goes off when releasing the brake pedal.
  NG: INSPECT STOP LAMP SWITCH CIRCUIT (SEE DTC C1249/49: OPEN CIRCUIT IN STOP LIGHT SWITCH CIRCUIT )
OK: Go to next step.
INSPECT STOP LAMP SWITCH ASSY
1. Turn the ignition switch off.
2. Disconnect the stop lamp switch assy connector.
  
  Fig 1: Disconnecting Stop Lamp Switch Assy Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Measure the resistance according to the value(s) in Fig 2 .
Standard:

Fig 2: Stop Lamp Switch Assy Specifications Chart
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE STOP LAMP SWITCH ASSY (SEE PEDAL RESERVE DISTANCE )

OK: Go to next step.
INSPECT ECM
1. Reconnect the stop lamp switch assy connector.
2. Disconnect the E7 connector of the ECM.
  
  Fig 3: Disconnecting E7 Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Turn the ignition switch to the ON position.
4. Measure the voltage according to the value(s) in Fig 4 .
  Standard:
  
  Fig 4: Measuring Voltage
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. Measure the voltage according to the value(s) in Fig 6 .
  
  Fig 5: Measuring Voltage Between ST1 & Body Ground
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Standard:
  
  Fig 6: Measuring Voltage Between ECM & Body Ground Specifications Chart
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LAMP SWITCH ASSY - ECM)
  
  OK: REPLACE ECM (SEE REPLACEMENT )