Diagnosis System

DIAGNOSIS FUNCTION

The diagnosis function makes the master warning light and the multi-information display come on, and the cruise main indicator light blinks as shown in the illustration. When a malfunction occurs in the dynamic radar cruise control system, the DTCs are stored in the ECM.

TEXT IN ILLUSTRATION

*a	Multi-information Display
*b	Master Warning Light
*c	Cruise Main Indicator Light (Constant speed control mode)
*d	Cruise Main Indicator Light (Vehicle-to-vehicle distance control mode)

Fig 1: Identifying Master Warning Light, Multi-Information Display And Cruise Main Indicator Light

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NOTE:

The master warning light turns off if the system returns to normal condition.

Fig 2: Identifying Cruise Main Indicator Light On/Off Intervals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Since the stored data in the ECM is cleared by disconnecting the EFI and ETCS fuses or the battery terminal, do not disconnect them until the inspection has been completed.

DESCRIPTION
1. The ECM controls the dynamic radar cruise control system of the vehicle. The data and DTCs relating to the dynamic radar cruise control system can be read from the DLC3 of the vehicle. If the cruise main indicator light does not come on after the DTC check, there may be a problem with either the combination meter or the CAN communication systems. Use the Techstream to check and solve the problem.
CHECK DLC3
1. Check the DLC3. Refer to DTC CHECK / CLEAR .

CHECK INDICATOR

Turn the ignition switch to ON.

Fig 3: Identifying Cruise Main Indicator Light And READY Indicator Light
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Check that the cruise main indicator light and READY indicator light come on when the main switch ON-OFF button is pushed on, and that the indicator light and the indicator go off when the ON-OFF button is pushed off.
HINT:
- If the indicator check result shows a problem, proceed to troubleshooting the combination meter.
- If a malfunction occurs in the vehicle speed sensors, the stop light switch, or other related parts during cruise control driving, the ECU actuates AUTO CANCEL of the cruise control and blinks the cruise main indicator light. This indicator light informs the driver of the malfunction. At the same time, the malfunction is stored as a diagnostic trouble code.
  
  Fig 4: Identifying Cruise Main Indicator Light On/Off Intervals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Cruise Main Indicator Light (Vehicle-to-vehicle distance control mode)
*b	READY Indicator Light