Protocol
SW-CAN and GMLAN (SAE J2411)
SW-CAN (Single Wire CAN, SAE J2411) is a single-wire CAN bus used by General Motors and Opel, also known as GMLAN. On the OBD socket it runs on pin 1, at 33.3 kbit/s in normal operation and 83.3 kbit/s for module programming.
Reviewed by Daniel Morales, founder of Reprorace SL, on
Key facts at a glance
| Protocol | Standard | J1962 pins | Speed or link | ECO-LITE | ECO-LITE TOOL | ECOPRO Gen4 |
|---|---|---|---|---|---|---|
| SW-CAN (GMLAN) | SAE J2411 | 1 | 33.3 and 83.3 kbit/s | Yes | Reproduces the vehicle's | Yes |
| CAN | ISO 15765-4 · ISO 11898 | 6 and 14 (2nd channel on 3 and 11; classic CAN on 1 and 9) | 125, 250 and 500 kbit/s | Yes: 2 channels and pins 1/9 | Reproduces the vehicle's | Multichannel |
Data from the device catalog and the standards cited. The devices are in pre-production: figures may be adjusted after the first units have been validated.
When you need it
- GM and Opel vehicles with body or comfort modules on SW-CAN
- GM module programming that requires high-speed mode
- Cars with a signal on pin 1 and pin 9 free, where GMLAN is tried first
Which Diaglana device covers it, and its limits
- ECO-LITE
- SW-CAN on pin 1, at 33.3 and 83.3 kbit/s. It checks whether pin 1 carries a bus or a voltage before using it.
- ECO-LITE TOOL
- Reproduces the remote car's SW-CAN for your tool.
- ECOPRO Gen4
- SW-CAN in the workshop station. In development.
Frequently asked questions
Are SW-CAN and GMLAN the same thing?
GMLAN is General Motors' name for its network, which uses SAE J2411 single-wire CAN at low speed. In diagnostics, both names are used for the bus on pin 1.
Why does it have two speeds?
33.3 kbit/s is the normal speed, and 83.3 kbit/s is used to program modules faster.
Do I need SW-CAN if my car isn't a GM or Opel?
Usually not. If pin 1 on your socket carries something else, ECO-LITE detects it and doesn't treat it as SW-CAN.
Want to try it in your workshop?
Check the device page for the full specifications, or buy in the shop at the final price.