Diagnosis System

WARNING: This page is about a different car, the 2006 Toyota Tundra and 2005 Toyota Tundra. However, it is still accessible from the selected car via links, so may be relevant.

DESCRIPTION
The ECM controls the cruise control system of the vehicle. The data and DTCs relating to the cruise control system can be read from the DLC3 of the vehicle. If no DTCs are output when checking for DTCs, there may be a problem with the combination meter or the multiplex communication system.

Use the hand-held tester or SST to check and solve the problem.

SST 09843-18040

Fig 1: Using Hand-Held Tester Or SST To Check And Solve Problem
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

CHECK THE DLC3

The vehicle's ECM uses ISO 9141-2 for communication. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.

Fig 2: Identifying DLC3 Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

RESISTANCE SPECIFICATION

Symbols (Terminals No.)	Terminal Description	Condition	Specified Condition
SIL(7) - SG(5)	Bus "+" line	During transmission	Pulse generation
CG(4) - Body ground	Chassis ground	Always	Below 1 Ω
SG(5) - Body ground	Signal ground	Always	Below 1 Ω
BAT(16) - Body ground	Battery positive	Always	11 to 14V

HINT:

If the display shows "UNABLE TO CONNECT TO VEHICLE" when you have connected the hand-held tester to the DLC3, turned the ignition switch to the ON position and operated the tester, there is a problem on either the vehicle side or the tool side.

If communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
If communication is still impossible when the tool is connected to another vehicle, the problem is probably in the tool itself, so consult the Service Department listed in the tool's instruction manual.

CHECK THE INDICATOR
1. Turn the ignition switch to the ON position.
2. Check that the CRUISE main indicator light comes on when the cruise control main switch ON-OFF button is pushed on, and that the indicator light goes off when the ON-OFF button is pushed off.
Fig 3: Checking CRUISE Main Indicator Light
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

If there is a problem with the indicator, inspect the CRUISE MAIN INDICATOR LIGHT CIRCUIT .

HINT:

If a malfunction occurs in the vehicle speed sensors, stop lamp switch assy, or other related parts during cruise control driving, the ECM actuates AUTO CANCEL of the cruise control and then the CRUISE main indicator light starts to blink, informing the driver of the malfunction. At the same time, data of the malfunction is stored as a diagnostic trouble code (DTC).

Fig 4: CRUISE Main Indicator Light Blinking Pattern
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002