Cruise Control System - Diagnostics: Pre-Check

1. Description

   The ECM stores trouble codes. The diagnosis system allows for reading of the trouble codes from the DLC3. If the CRUISE MAIN indicator light does not come on after DTC check, it means a malfunction has occurred in the cruise control system.

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

2. Check the DLC3.

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

   Fig 1: Identifying DLC3 Terminals CG And TC

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TERMINAL AND SPECIFIC CONDITION
   
   

   Terminal No.	Tester connection/Specification	Condition
   4	Chassis Ground - Body Ground / 1 Ω or less	Always
   7	Bus + Line / Pulse generation	During Communication
   16	Battery Positive - Body Ground / 9 to 14 V	Always

   HINT:

   If the display shows "UNABLE TO CONNECT TO VEHICLE" after connecting the hand-held tester to the DLC3 and turning the ignition to the ON position, there is a problem either with the vehicle or the tool. (Hand held tester ONLY)

   • If communication is normal when connecting the tool to another vehicle, inspect the DLC3 on the original vehicle.
   • If communication is still not possible when connecting the tool to another vehicle, it suggests the problem is the tool's own. In this case, consult the Service Department listed in the tool's instruction manual.
3. 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.

HINT:

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

Fig 2: Locating Indicator Cruise Control Main Switch

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002