Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSTOYOTA20254RUNNER SR5, RWDREPAIR AND DIAGNOSIS (SINGLE PAGE)GENERAL INFORMATIONTOWINGTRAILER BRAKE CONTROL SYSTEM - DIAGNOSTIC CODES & SYMPTOM TESTSTRAILER BRAKE CONTROL SYSTEMDTC U0076-88: CONTROL MODULE COMMUNICATION BUS "D" OFF BUS OFF; DTC U0077-88: CONTROL MODULE COMMUNICATION BUS "E" OFF BUS OFF; DTC U0078-88: CONTROL MODULE COMMUNICATION BUS "F" OFF BUS OFF; DTC U0129-87: LOST COMMUNICATION WITH BRAKE SYSTEM CONTROL MODULE "A" MISSING MESSAGE; DTC U0155-87: LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER (IPC) CONTROL MODULE MISSING MESSAGE; DTC U1170-87: LOST COMMUNICATION WITH BRAKE SYSTEM CONTROL MODULE (CH2) MISSING MESSAGE; DTC U1171-87: LOST COMMUNICATION WITH BRAKE SYSTEM CONTROL MODULE (CH3) MISSING MESSAGE [12/2024 - ]DESCRIPTION
2025 Toyota 4Runner SR5, RWD
DTC U0076-88: Control Module Communication Bus "D" Off Bus Off; DTC U0077-88: Control Module Communication Bus "E" Off Bus Off; DTC U0078-88: Control Module Communication Bus "F" Off Bus Off; DTC U0129-87: Lost Communication with Brake System Control Module "A" Missing Message; DTC U0155-87: Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message; DTC U1170-87: Lost Communication with Brake System Control Module (ch2) Missing Message; DTC U1171-87: Lost Communication with Brake System Control Module (ch3) Missing Message [12/2024 - ]: Description
2025 Toyota 4Runner SR5, RWDSECTION Description
The following DTCs are output when there is a communication malfunction between a sensor or ECU.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from | Priority |
|---|---|---|---|---|---|
| U0076-88 | Control Module Communication Bus "D" Off Bus Off | Bus off condition continues for 1 second or more.*1 | CAN communication system | Trailer Brake Controller | B |
| U0077-88 | Control Module Communication Bus "E" Off Bus Off | Bus off condition continues for 1 second or more.*2 | CAN communication system | Trailer Brake Controller | B |
| U0078-88 | Control Module Communication Bus "F" Off Bus Off | Bus off condition continues for 1 second or more | CAN communication system | Trailer Brake Controller | B |
| U0129-87 | Lost Communication with Brake System Control Module "A" Missing Message |
|
|
Trailer Brake Controller | B |
| U0155-87 | Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message | With a vehicle speed of 6 km/h (4 mph), the system is continuously unable to receive data from the combination meter assembly for 5 seconds or more. |
|
Trailer Brake Controller | B |
| U1170-87 | Lost Communication with Brake System Control Module (ch2) Missing Message | The trailer brake control ECU (brake control with bracket relay) is continuously unable to receive data from the No. 2 skid control ECU (brake actuator assembly) for 1 second or more.*2 |
|
Trailer Brake Controller | B |
| U1171-87 | Lost Communication with Brake System Control Module (ch3) Missing Message | The trailer brake control ECU (brake control with bracket relay) is continuously unable to receive data from the skid control ECU (brake actuator assembly) for 1 second or more.*1 |
|
Trailer Brake Controller | B |
*1: for Gasoline Model
*2: except Gasoline Model
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.