Inspection Procedure

1. Disconnect the E55 connector.
2. Measure the voltage according to the value (s) in the table below.

Standard Voltage 

Fig 1: Identifying E55 Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

If any of the ECUs specified in the wiring diagram supplies power to the combination meter, the combination meter will output a waveform.

NG: Go to step  5

OK: Go to Next Step 

1. Reconnect the E55 connector.
   1. Disconnect the A39*1 or A38*2 connector.
   2. Measure the voltage according to the value (s) in the table below.

   Standard Voltage 

   VOLTAGE SPECIFICATION
   
   

   Tester Connection	Switch Condition	Specified Condition
   A39-22 (SP1)(1) - Body ground	Ignition switch ON	11 to 14 V
   A38-11 (SP1)(2)- Body ground	Ignition switch ON	11 to 14 V
   (1) w/o VSC (2) w/ VSC

   Fig 2: Identifying Skid Control ECU Connector Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG: Go to step  4

   OK: Go to Next Step 

1. Check the input waveform.
   1. Reconnect the A39*1 or A38*2 connector.
   2. Remove the combination meter with the connector (s) still connected.
   3. Connect the oscilloscope to terminal E55-35 (SI) and body ground.
   4. Turn the ignition switch to ON.
   5. Turn a drive wheel slowly.
   6. Check the signal waveform according to the condition (s) in the table below.
   ITEM CONDITION CHART
   
   

   Item	Condition
   Tool setting	5V/DIV., 20 ms./DIV.
   Vehicle condition	Driving at approx. 20 km/h (12 mph)

   • *1:w/o VSC
   • *2:w/ VSC

   OK: 

   The waveform is displayed as shown in the illustration  .

   HINT:

   When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.

   Fig 3: Inspecting Skid Control ECU

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Result 

   RESULT REFERENCE
   
   

   Result	Proceed to
   OK	A
   NG (w/o VSC)	B
   NG (w/ VSC)	C

   B: REPLACE SKID CONTROL ECU (w/o VSC)  (See INSTALLATION )

   C: REPLACE SKID CONTROL ECU (w/ VSC)  (See INSTALLATION )

   A: REPLACE COMBINATION METER ASSEMBLY (See  COMBINATION METER  ) 

1. Disconnect the E55 connector.
2. Measure the resistance according to the value (s) in the table below.

Standard Resistance 

Fig 4: Identifying E55 Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: REPLACE COMBINATION METER ASSEMBLY (See  COMBINATION METER  ) 

1. Inspect for a short in the circuits connected to the combination meter shown in the wiring diagram.

   HINT:

   If voltage is not present, it is possible that an ECU or circuit has a malfunction. The malfunctioning ECU or circuit will be diagnosed in the following steps.

   1. Disconnect the E55 and 2E and E32 (*1) and E52 (*2) and E44 (*3) connectors.
   2. Measure the resistance according to the value (s) in the table below.

Standard Resistance 

Fig 5: Identifying Tire Pressure Warning ECU Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

• *1: w/Radio Receiver
• *2: w/ Navigation Receiver Assembly
• *3: w/ Tire Pressure Warning System

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to Next Step 

HINT:

For vehicles not equipped with a tire pressure warning system, proceed to the next step.

1. Reconnect the E44 connector.
2. Measure the resistance according to the value (s) in the table below.

Standard Resistance 

Fig 6: Identifying Tire Pressure Warning ECU Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

If the result is not as specified, there may be a short in the tire pressure warning ECU.

NG: REPLACE TIRE PRESSURE WARNING ECU  (See INSTALLATION )

OK: Go to Next Step 

HINT:

For vehicles not equipped with a radio receiver, proceed to the next step.

1. Reconnect the E32 connector.
2. Measure the resistance according to the value (s) in the table below.

Standard Resistance 

Fig 7: Identifying Radio Receiver Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

If the result is not as specified, there may be a short in the radio receiver.

NG: REPLACE RADIO RECEIVER 

OK: Go to Next Step 

1. Reconnect the E52 connector.
2. Measure the resistance according to the value (s) in the table below.

Standard Resistance 

Fig 8: Identifying Navigation Receiver Assembly Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

If the result is not as specified, there may be a short in the navigation receiver assembly.

NG: REPLACE NAVIGATION RECEIVER ASSEMBLY 

OK: Go to Next Step 

1. Inspect for a short in the circuit that is connected to the combination meter shown in the wiring diagram.

   HINT:

   If voltage is not present, it is possible that an ECU or circuit has a malfunction. The malfunctioning ECU or circuit will be diagnosed in the following steps.

   1. Disconnect the 2C, 2D, and 2E connectors.
      Fig 9: Identifying Instrument Panel Junction Block Connector Terminal

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Measure the voltage according to the value (s) in the table below.

   Standard Voltage 

   VOLTAGE SPECIFICATION
   
   

   Tester Connection	Switch Condition	Specified Condition
   2C-8(2) - Body ground	Ignition switch ON	4.5 to 14 V
   2D-8 - Body ground	Ignition switch ON	4.5 to 14 V
   2E-1(1) - Body ground	Ignition switch ON	4.5 to 14 V
   (1) w/ Navigation System (2) w/ Sliding Roof

   Result 

   RESULT REFERENCE
   
   

   Result	Proceed to
   All values are within the specified range.	A
   Malfunction between the ECM and instrument panel junction block.	B
   Malfunction between the sliding roof control ECU and instrument panel junction block. Malfunction between the stereo component amplifier and instrument panel junction block.	C

   B: Go to Next Step 

   C: Go to step  11

   A: REPLACE INSTRUMENT PANEL JUNCTION BLOCK 

1. Disconnect the A37 connector.
2. Measure the resistance according to the value (s) in the table below.

Standard Resistance 

Fig 10: Identifying A37 ECM Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Result 

B: REPLACE ECM (for 2ZR-FE)  (See REMOVAL )

C: REPAIR OR REPLACE HARNESS OR CONNECTOR 

A: REPLACE ECM (for 2AZ-FE)  (See REMOVAL )

HINT:

For vehicles not equipped with a sliding roof, proceed to the next step.

1. Reconnect the 2C, 2D, and 2E connectors.
2. Disconnect the 02 connector.
3. Turn the ignition switch to ON.
4. Check that the speed signal circuit operates normally.

Fig 11: Identifying 02 Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Result 

HINT:

If the speed signal circuit operates normally after disconnecting the sliding roof control ECU, there may be a short in the sliding roof control ECU.

NG: Go to Next Step 

OK: REPLACE SLIDING ROOF CONTROL ECU  (See DISASSEMBLY )

HINT:

For vehicles not equipped with a stereo component amplifier, proceed to the next step.

1. Reconnect the 2C, 2D, and 2E connectors.
2. Disconnect the E34 connector.
3. Turn the ignition switch to ON.
4. Check that the speed signal circuit operates normally.

Fig 12: Identifying Stereo Component Amplifier Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Result 

HINT:

If the speed signal circuit operates normally after disconnecting the stereo component amplifier, there may be a short in the stereo component amplifier.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: REPLACE STEREO COMPONENT AMPLIFIER