DESCRIPTION If a
malfunction is detected in the power supply circuit, the trailer brake
control ECU (brake control with bracket relay) stores this DTC. |
DTC No. | Detection Item |
INF Code | DTC Detection Condition |
Trouble Area | | C1241 |
Power Supply Voltage Circuit |
81 82 |
- INF Code: 81 (Low power supply voltage malfaunction)
- At a vehicle speed of 3 km/h or higher, the IG terminal voltage is continuously below 7.9 V for 5 seconds or more
- INF Code: 82 (High power supply voltage malfaunction)
- The IG terminal voltage continuously exceeds 17.8 V for 5 seconds or more with the ignition switch on
|
- Trailer brake control ECU (Brake control with bracket relay)
- Harness or connector
- ECU-IG1 NO.2 fuse
| WIRING DIAGRAM
 CAUTION / NOTICE / HINT
NOTICE: Inspect the fuses for circuits related to this system before performing the following procedure. PROCEDURE
(a) Check the battery voltage.
Standard Voltage: |
Tester Connection | Condition |
Specified Condition | |
Positive (+) terminal - Negative (-) terminal |
Ignition switch off | 11 to 14 V |
| NG |
 | CHECK OR REPLACE CHARGING SYSTEM COMPONENT OR BATTERY |
|
OK |
 | |
| 2. |
CHECK TERMINAL VOLTAGE (IG TERMINAL) |
| (a) Turn the ignition switch off. |
 |
|
*a | Front view of wire harness connector
(to Trailer Brake Control ECU (Brake Control with Bracket Relay)) | | |
(b) Disconnect the J172 trailer brake control ECU (brake control with bracket relay) connector.
(c) Inspect both the connector case and the terminal for deformation and corrosion.
OK: No deformation or corrosion. (d) Turn the ignition switch to ON.
(e) Measure the voltage according to the value(s) in the table below. Standard Voltage: |
Tester Connection | Condition |
Specified Condition | |
J172-13 (IG) - Body ground |
Ignition switch ON | 11 to 14 V |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) |
|
OK | |
| |
| 3. |
CHECK HARNESS AND CONNECTOR (GND TERMINAL) |
| (a) Turn the ignition switch off. |
 |
|
*a | Front view of wire harness connector
(to Trailer Brake Control ECU (Brake Control with Bracket Relay)) | | |
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
J172-20 (GND) - Body ground |
Always | Below 1 Ω |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT) |
|
OK | |
| |
(a) Reconnect the J172 trailer brake control ECU (brake control with bracket relay) connector.
(b) Clear the DTCs. Click here 
(c) Turn the ignition switch off. (d) Turn the ignition switch to ON.
(e) Perform a road test. (f) Check if the same DTC is output. Click here
|
Result | Proceed to | |
DTCs C1241 is not output. |
A | | DTCs C1241 is output. |
B |
| A |
| USE SIMULATION METHOD TO CHECK |
| B |
| REPLACE BRAKE CONTROL WITH BRACKET RELAY | | 
