What does this module do?
A smart junction box replaces conventional fuses and relays with semiconductor switches and measures the current of each output. Since power distribution happens here, a problem in this module can affect many seemingly unrelated modules at once.
What do the makes call this module?
The name of a module doing the same job changes from make to make. The names below are the actual definition names used under this type in the CarCoding scan map (10 distinct names):
| Module name | Address |
|---|---|
| BCC (comfort) | 7B4 |
| BPCM | 700 |
| Engine Fuse Box (29-bit) | 18DA42F2 |
| Engine Fuse Box (USM) | 74D |
| FEM (Front Electronic Module) | 784 |
| Intelligent power distribution module (IPDM) | 74D |
| REM (Rear Electronic Module) | 771 |
| SJB (Smart Junction Box) | 771 |
| Service Box (BSE) | 759 |
| Service Box (BSS) | 754 |
Which makes define it?
The map holds 10 definitions for this type, spread across 6 make groups:
Address and protocol
Every definition in the map is marked as UDS. 9 of the addresses are 11-bit CAN identifiers (three digits, such as 7E0) and 1 are 29-bit extended identifiers (such as 18DA10F1). The most frequent addresses for this type are: 74D (2), 771 (2), 18DA42F2 (1), 700 (1).
Related fault codes
Fault codes stored in this module usually belong to these groups:
Looking for what a fault code means? Fault code library.
Other module types
Junction Box Module on your own vehicle
With an ELM327-based BLE OBD2 adapter, CarCoding scans the vehicle’s modules, reads fault codes from those it can reach and explains every code in plain language. Which modules are reachable depends on the make and on the vehicle. The app is free to download.
Some advanced features require an in-app purchase.
Data source: the CarCoding ECU scan map (ecuDatabase.ts). The addresses and names in the table are definitions from the map; they can differ depending on the hardware and software version in your vehicle.