P1631

CRUISE CONTROL: DYNAMIC LASER CRUISE CONTROL SYSTEM: P1631: Communication Error from ECM to VSC

DTC P1631 - Communication Error from ECM to VSC

DESCRIPTION

The ECM sends signals such as A/T information signals, dynamic laser cruise control operation signals, brake operation demand signals, and buzzer operation demand signals to the skid control ECU when the dynamic laser cruise control is in operation. The ECM is the only component that has a function to record and output the DTCs in the dynamic laser cruise control system. Therefore, if the skid control ECU detects a communication error from the ECM, it sends a malfunction signal back to the ECM.





INSPECTION PROCEDURE

HINT: This circuit uses CAN communication. Therefore, if there are any malfunctions in the communication circuit, one or more DTCs in the CAN communication system are output.

NOTE: When the distance control ECU and ECM is replaced with a new one, initialization must be performed Programming and Relearning.

PROCEDURE

1. REPLACE ECM
(a) Replace the ECM.
- for 2UZ-FE Removal.
- for 3UR-FE Removal.
- for 3UR-FBE Removal.

NEXT -- Continue to next step.

2. PERFORM INITIALIZATION
(a) Perform initialization Programming and Relearning.
(1) Turn the ignition switch to ON.
(2) Turn the cruise control main switch on.
(3) With the brake pedal depressed, push the cruise control main switch to + (ACCEL)/RES (RESUME) 3 times within 3 seconds. Check that the skid control buzzer sounds at this time.

NOTICE:
- Do not turn the light control switch on at this time because the beam axis automatic adjustment mode has already started, which could lead to incorrect beam axis. If the light control switch is turned on by mistake, readjust the beam axis (refer to Beam Axis Adjustment) Adjustments.
- If initialization cannot be performed, first inspect the stop light switch circuit, cruise main switch circuit, and skid control buzzer circuit.

NEXT -- Continue to next step.

3. CLEAR DTC
(a) Clear the DTC Dynamic Laser Cruise Control System.
NEXT -- Continue to next step.

4. CHECK FOR DTC
(a) Reproduce the DTC detection conditions under which the DTC is stored.

HINT: If the DTC detection conditions are not correct, the system will not detect the trouble.

(b) Drive the vehicle at a speed of 45 km/h (28 mph) or more and turn the cruise control main switch ON. Push the -SET switch to activate the cruise control system.
(c) Check for DTCs Dynamic Laser Cruise Control System.
OK:
P1631 is not output.

NG -- REPLACE SKID CONTROL ECU
OK -- END