DESCRIPTION
The combination meter assembly receives vehicle speed signals from the skid control ECU via the CAN communication system. The speed sensor detects the wheel speed and sends the appropriate signals to the skid control ECU. The skid control ECU supplies power to the vehicle speed sensor. The skid control ECU detects vehicle speed signals based on pulses of the voltage.
Tech Tips
Factors that affect the indicated vehicle speed include the tire size, tire inflation, and tire wear. The speed indicated on the speedometer has an allowable margin of error. This can be tested using the GTS. For details about testing and the margin of error, see the reference chart Click here.
If the vehicle speed sensor circuit has a malfunction, the skid control ECU stores DTCs. Troubleshoot the Electronically Controlled Brake System Click here.
WIRING DIAGRAM
| *1 | Brake Booster with Master Cylinder Assembly (Skid Control ECU) |
| *2 | Combination Meter Assembly |
| *3 | CAN Communication Line |
CAUTION / NOTICE / HINT
Note
If the vehicle speed is outside the allowable range when tested, perform the on-vehicle inspection Click here.
Tech Tips
Before starting the following inspection, check tire size and tire air pressure.
PROCEDURE
CHECK CAN COMMUNICATION SYSTEM
Check if CAN communication DTCs are output Click here.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
GO TO CAN COMMUNICATION SYSTEM Click here |
| A |
|
PERFORM ACTIVE TEST USING GTS (SPEED METER OPERATION)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Enter the following menus: Body Electrical / Combination Meter / Active Test.
Check the operation by referring to the table below.
| Tester Display | Test Part | Control Range | Diagnostic Note |
|---|---|---|---|
| Speed Meter Operation | Speedometer | OFF, 0, 40, 80, 120, 160, 200, 240 km/h | There is a deviation in the values displayed on the speedometer display (Control range → Speedometer) Reference (except RHD without rear fog light): 40 → 41.7 to 46.2 80 → 83.4 to 88.4 120 → 125.1 to 130.6 160 → 166.2 to 173.2 200 → 207.7 to 215.7 240 → 249.2 to 258.0 Reference (for RHD without rear fog light): 40 → 41.0 to 45.5 80 → 82.1 to 87.1 120 → 123.1 to 128.1 160 → 164.1 to 169.1 200 → 205.1 to 210.1 240 → 246.2 to 251.2 |
| OK |
|---|
| Speedometer indication is normal. |
| NG |
|
REPLACE COMBINATION METER ASSEMBLY Click here |
| OK |
|
CHECK ELECTRONICALLY CONTROLLED BRAKE SYSTEM
Check if electronically controlled brake system DTCs are output Click here.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM Click here |
| A |
|
READ VALUE USING GTS (VEHICLE SPEED, VEHICLE SPEED METER)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Enter the following menus:
for ABS/VSC/TRC: Chassis / ABS/VSC/TRC / Data List.
for Combination Meter: Body Electrical / Combination Meter / Data List.
Check the values by referring to the table below.
| Tester Display | Measurement Item/Range | Normal Condition | Diagnostic Note |
|---|---|---|---|
| Vehicle Speed | Maximum wheel speed sensor reading/Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph) | Vehicle stopped: 0 km/h (0 mph) | When driving at constant speed: No large fluctuations |
| Tester Display | Measurement Item/Range | Normal Condition | Diagnostic Note |
|---|---|---|---|
| Vehicle Speed Meter | Vehicle speed/Min.: 0 km/h (0 mph), Max.: 255 km/h (158 mph) | Almost the same as actual vehicle speed | - |
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
When the Data List values of the ECUs match, an internal malfunction of the combination meter assembly is suspected.
When the Data List values of the ECUs do not match, a signal output error of the skid control ECU or an internal malfunction of the combination meter assembly is suspected.
| A |
|
REPLACE COMBINATION METER ASSEMBLY Click here |
| B |
|
REPLACE COMBINATION METER ASSEMBLY
Replace the combination meter assembly with a new one Click here.
| OK |
|---|
| The operation of the speedometer returns to normal. |
| Result | ||||||||
|---|---|---|---|---|---|---|---|---|
|
| A |
|
END |
| B |
|
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SKID CONTROL ECU) Click here |
| C |
|
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SKID CONTROL ECU) Click here |