Toyota: Possible issue with DSU disconnecting on openpilot 0.9.8+ (Prius longitudinal control & enableDsu)

[eFiniLan]

I've been testing Toyota Prius on openpilot versions 0.9.8 and above (mainly for SDSU porting), and some users have reported a “horse riding” effect (alternating acceleration and deceleration).

After some careful testing, I found that if the DSU is completely disconnected, a cruise fault occurs. This led me to suspect the following:

• The issue may not be related to SDSU porting itself.
• The enableDsu implementation may have issues, which could be causing the cruise fault.
• There may be a longitudinal tuning issue specifically with the Toyota Prius (some SDSU users are Prius owners).

Questions

• Have you received any recent reports/logs from Toyota Prius owners running openpilot 0.9.8+ with longitudinal control enabled?
• Could you check if the enableDsu functionality might not be working as expected?

I’ve attached logs from two different Toyota Prius vehicles running with DSU disconnected for reference.

800808aede841985/00000000--d48b541b97 7594f32730b32394/00000002--4e37f9de1b

[sshane]

Unplugging the DSU has never been a great experience. I remember 3+ years ago the car would always fault on the first startup due to fingerprint time and the delayed start, you then had to turn the car off, wait 5m and turn it back on. It's definitely possible that startup time has gotten slower over the years lessening the reliability of unplugged DSU setups further.

The real solution is figuring out how to stop tx of the DSU on startup like we do for the radar on other cars.

[eFiniLan]

Unplugging the DSU has never been a great experience. I remember 3+ years ago the car would always fault on the first startup due to fingerprint time and the delayed start, you then had to turn the car off, wait 5m and turn it back on. It's definitely possible that startup time has gotten slower over the years lessening the reliability of unplugged DSU setups further.

The real solution is figuring out how to stop tx of the DSU on startup like we do for the radar on other cars.

Thanks Shane!