> For the complete documentation index, see [llms.txt](https://wiki.retropilot.org/index/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.retropilot.org/index/vehicles/volkswagen-pq25-platform-retrofits/electrical-platforms-tl-dr.md).

# Electrical Platforms TL;DR

### PQ25

It's similar on a network level to PQ35 vehicles however it has an integrated CAN BUS Gateway, this means harnesses like J533 will not work.

### PQ26

This platform is the successor to PQ25, this platform speaks both in MQB and PQ's CAN BUS messages, the extent of which hasn't been explored, the most important thing to know is the EPS should be running MQB firmware. This also has an integrated CAN BUS gateway, therefore J533 harnesses will not work.

### MQB-A0

This platform is the successor to PQ26, this platform does not have the interoperability as seen in PQ26. This has a dedicated CAN BUS gateway, therefore J533 harnesses will work.​

| Platform | J533 Harness | PQ Messaging | MQB Messaging |
| -------- | ------------ | ------------ | ------------- |
| PQ25     | NO           | YES          | NO            |
| PQ26     | NO           | YES          | YES           |
| MQB-A0   | YES          | NO           | YES           |


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