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.

HINT:

If DTCs related to different system that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.
Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.

READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL (ENGINE COOLANT TEMPERATURE)
1. Connect the hand-held tester or the OBD II scan tool to the DLC3.
2. Turn the ignition switch to ON and turn the hand-held tester or the OBD II scan tool ON.
3. On the hand-held tester or the OBD II scan tool, select the item: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP. Read the values.
  Temperature: 80°C to 97°C (176 to 207°F) after warming up.
  
  Result:
  
  Fig 1: Temperature Displayed Result Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
HINT:
- If there is an open circuit, the hand-held tester or the OBD II scan tool indicates -40°C (-40°F).
- If there is a short circuit, the hand-held tester or the OBD II scan tool indicates 140°C (284°F) or more.
B: Go to step 2

C: CHECK FOR INTERMITTENT PROBLEMS (See CHECK FOR INTERMITTENT PROBLEMS )

A: GO TO NEXT STEP.
READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL (CHECK FOR OPEN IN WIRE HARNESS)
1. Disconnect the E3 engine coolant temperature sensor connector.
2. Connect terminals 1 and 2 of the engine coolant temperature sensor wire harness side connector.
3. Turn the ignition switch to ON and turn the hand-held tester or the OBD II scan tool ON.
4. On the hand-held tester or the OBD II scan tool, select the item: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP. Read the values.
  Temperature: 140°C (284°F) or more
5. Reconnect the engine coolant temperature sensor connector.
  
  Fig 2: Disconnecting E3 Engine Coolant Temperature Sensor Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 3: Identifying Engine Coolant Temperature Sensor Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: CONFIRM GOOD CONNECTION AT SENSOR. IF OK, REPLACE ENGINE COOLANT TEMP. SENSOR

NG: GO TO NEXT STEP.
READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL (CHECK FOR OPEN IN ECM)
1. Disconnect the E3 engine coolant temperature sensor connector.
2. Connect terminals THW and E2 of the E10 ECM connector.
  HINT: Before checking, do a visual and contact pressure check for the ECM connector.
3. Turn the ignition switch to ON and turn the hand-held tester or the OBD II scan tool ON.
4. On the hand-held tester or the OBD II scan tool, select the item: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP. Read the values.
  Temperature: 140°C (284°F) or more
5. Reconnect the engine coolant temperature sensor connector.
  
  Fig 4: Connecting Terminals THW And E2 Of E10 ECM Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 5: Identifying ECM Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: REPAIR OR REPLACE HARNESS OR CONNECTOR

NG: GO TO NEXT STEP.

CONFIRM GOOD CONNECTION AT ECM. IF OK, REPLACE ECM (See ECM (3MZ-FE) )
READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL (CHECK FOR SHORT IN WIRE HARNESS)
1. Disconnect the E3 engine coolant temperature sensor connector.
2. Turn the ignition switch to ON and turn the hand-held tester or the OBD II scan tool ON.
3. On the hand-held tester or the OBD II scan tool, select the item: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP. Read the values.
  Temperature: -40°C (-40°F)
4. Reconnect the engine coolant temperature sensor connector.
  
  Fig 6: Disconnecting E3 Engine Coolant Temperature Sensor Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: REPLACE ENGINE COOLANT TEMPERATURE SENSOR

NG: GO TO NEXT STEP.
READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL (CHECK FOR SHORT IN ECM)
1. Disconnect the E10 ECM connector.
2. Turn the ignition switch to ON and turn the hand-held tester or the OBD II scan tool ON.
3. On the hand-held tester or the OBD II scan tool, select the item: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / COOLANT TEMP. Read the values.
  Temperature: -40°C (-40°F)
4. Reconnect the ECM connector.
  
  Fig 7: Disconnecting E10 ECM Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 8: Connecting E10 ECM Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: REPAIR OR REPLACE HARNESS OR CONNECTOR

NG: GO TO NEXT STEP.

REPLACE ECM (See ECM (3MZ-FE) )