Toyota Tacoma 2015-2018 Service Manual: Brake Control Signal Mismatch (C1A69)
DESCRIPTION
The skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2 sends signals to the millimeter wave radar sensor assembly according to the brake control status. If the millimeter wave radar sensor assembly receives a vehicle stability control system malfunction signal from the skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2, it will store DTC C1A64.
- *1: for Hydraulic Brake Booster
- *2: for Vacuum Brake Booster
|
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
|---|---|---|---|
|
C1A69 |
Brake Control Signal Mismatch |
While the ignition switch is ON, the millimeter wave radar sensor assembly receives a vehicle stability control system malfunction signal from the skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2 for 1 second or more. |
|
- *1: for Hydraulic Brake Booster
- *2: for Vacuum Brake Booster
CAUTION / NOTICE / HINT
NOTICE:
- When replacing the millimeter wave radar sensor assembly, always replace it with a new one. If a millimeter wave radar sensor assembly which was installed to another vehicle is used, the information stored in the millimeter wave radar sensor assembly will not match the information from the vehicle. As a result, a DTC may be stored.
- If the millimeter wave radar sensor assembly has been replaced, be sure
to perform millimeter wave radar sensor assembly adjustment.
Click here
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- The pre-collision system uses the CAN communication system. First, confirm
that there are no malfunctions in the CAN communication system. Refer to
How to Proceed with Troubleshooting.
Click here
PROCEDURE
|
1. |
CHECK FOR DTCs (VEHICLE STABILITY CONTROL SYSTEM) |
HINT:
Pre-collision system DTC C1A69 may be stored due to a malfunction in the vehicle stability control system. Therefore, it is necessary to check for and troubleshoot vehicle stability control system DTCs first.
(a) Check for DTCs.
Click here
|
Result |
Proceed to |
|---|---|
|
Vehicle stability control system DTCs are not output |
A |
|
Vehicle stability control system DTCs are output |
B |
| B | .gif) |
GO TO VEHICLE STABILITY CONTROL SYSTEM |
|
.gif)
|
2. |
CHECK FOR DTCs (PRE-COLLISION SYSTEM) |
(a) Clear the DTCs.
Click here
(b) Make sure that the DTC detection conditions are met.
HINT:
If the detection conditions are not met, the system cannot detect the malfunction.
(c) Check for DTCs.
Click here
|
Result |
Proceed to |
|---|---|
|
DTC C1A69 is not output |
A |
|
DTC C1A69 is output |
B |
| A | |
USE SIMULATION METHOD TO CHECK |
| B | |
REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY |
Other System Malfunction (C1A63)
DESCRIPTION
The millimeter wave radar sensor assembly receives accelerator pedal position
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Skid Control Buzzer Circuit (C1A4A)
DESCRIPTION
The millimeter wave radar sensor assembly is connected to the forward recognition
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The millimeter wave radar sensor assembly operates the pre-collision ala ...
Other materials:
How To Proceed With Troubleshooting
CAUTION / NOTICE / HINT
HINT:
Perform the following procedure to troubleshoot the dynamic radar cruise
control system.
*: Use the Techstream.
PROCEDURE
1.
VEHICLE BROUGHT TO WORKSHOP
NEXT
...
Reassembly
REASSEMBLY
PROCEDURE
1. INSTALL STARTER ARMATURE ASSEMBLY
(a) Install the starter armature to the starter yoke.
2. INSTALL STARTER BRUSH HOLDER ASSEMBLY
(a) Install the starter brush holder assembly.
(b) Connect the 4 brushes to the starter brush holder assembly.
(1) Using a scre ...
Inspection
INSPECTION
PROCEDURE
1. INSPECT GENERATOR BRUSH HOLDER ASSEMBLY
(a) Using a vernier caliper, measure the brush length.
Text in Illustration
*a
Length
Standard exposed length:
9.5 to 11.5 mm (0.374 to 0.453 in.)
Minimum ex ...