So I just upgraded to 2010 fit and I've been having issues with the eps. On the highway the steering feels super squirrelly and hard to keep straight when running the scanner I pulled these codes. Not quite sure what to do moving forward. Any help would be very appreciated.

 

I might start with voltage checks like ensuring grounds are good and battery/alternator checks. From what I've heard and read, EPS is a pretty substantial current draw. If it turns out to be actual EPS issue, I couldn't offer any suggestions.

 

It has a 70A fuse and supply wiring of similar thickness to the starter, so yes. Measuring the voltage across the heavy supply wires at the EPS control unit (heavy black and heavy white wires) while under load (turning the wheel while stopped) should be a good catch-all test.

However, the Honda service manual lists DTC 11-02 as "Low/high IG1-terminal voltage". That terminal acts as a signal to turn the EPS system on when the ignition is switched on. It may power the controller electronics, but doesn't do any of the heavy-lifting of moving the motor/steering. The troubleshooting is all about checking for wiring issues with that signal. After the ignition switch, it goes through fuse no. 11 in the dash fuse box, exits on pin A32 (purple wire), enters the EPS control unit at pin A1.

Diagnostics for DTC 35-02 start with clear the DTCs, turn the ignition to LOCK, start the engine, check for the DTC again. If the DTC doesn't come back, just ignore it. If it does come back, check for loose terminals on the EPS control unit connectors (I would also try unplugging/replugging them a few times to scrape off any possible oxidation on the contact points). Repeat the clear/re-check operation. If the DTC comes back, replace the EPS control unit.

Since both of those codes deal with connector/wiring issues, take a good hard look at your wiring.

 

I've done some testing. I cleared dtc and they didn't come back. But watching the eps live data the sub cpu voltage seems really low and jumps between 2v and 3.3v. looking at the ECU live data it says the eps signal is low?.

 

There's lots of EPS signals - that's not a useful label. Does it have some kind of ID or description if you select it on the scan tool?

There is a "Sub voltage" listed in the wiring connections (control unit pin B4). Looks like it's the torque sensor's secondary (redundant) signal, which should vary from 1.7V to 3.3V with steering wheel torque. The center (no torque) value should be about 2.5V. There's also a main signal on B2 that varies in the opposite direction.