FYI by leaving the 2 cables disconnected until the truck goes through self test allows the capacitors on the Q2 to charge before you hook up the power cables.

allow me to update,
seeing the only things i replaced before code23 showed up, was the rec2 and regen(q2),

I tried the old rec2, and... code 23 is gone! everything working great, no more code 23 or 2F for that matter (when plugging),

So... looks like the rec2 diode i received with the kit is the wrong one, but happy its done!

hey guys, had a similar problem with a near identical R40TT,

When plugging/slowing down with counter-throttle,

The truck would get jerky, and eventually throw a 2F code for regen, strangely enough, the speed limit would not be cut...

Anyhow,

Replaced the regen(q2) unit with a new one, as well as the rec2 diode that came with the kit,

I did as forktech418 suggested, connected the regen 3-pin connector to the power card, but the two main power leads, i left disconnected, and ran the first self-test,

I instantly got code 23, figured it was due to the the two power cables to the regen being disconnected,

Connected the two cables back on the regen, ran self-test again... still code 23!

So far I've looked over all the obvious stuff, but I am still getting code 23...

I tried hooking up the old regen(q2) unit again just now, just to check, and still have code 23...

Any input fellas?

Started with a code 2F (when plugging), and now I have a code 23 all the time...

When you replace a regen you should not connect the 2 power cables until after you have let the truck go through self test once.

Tip. The length of the battery cables or high resistance in the regen cabling can also produce this code.

Sounds like a regen fault with the symptoms and fault code. Have you checked the rest of the regen assy? Capacitor, resistor etc?

You didn't mention it but is you're batterie ok ?

You should always replace Q1 and REC1 as a "kit".

Before anyone asks. Yes. I've replaced the regen card.