Replaced clockspring on a 2008 prius, now something else is up?

First guess: improper installation; especially since it's your first time. BTDT

 

Either 1) you stressed the cable somehow during installation and some wires or pins broke, 2) the wiring harness in the column is damaged, 3) it's a really cheap new eBay knockoff part that broke already, 4) something else happened. It sounds like you need 30 minutes with a continuity tester. I'd start with testing the new cable. Like fotomoto says, first guess improper installation.

 

The clockspring assembly MUST be correctly timed to both the steering shaft and the steering wheel or it can be "over-wound" during turns.

Think of it this way: If you want to limit how far someone can open a water spigot, you could put a bolt thru one of the wheel holes so it would only rotate ~90* CCW. But what if someone who did not know what your intention was, took the wheel off to repack the seal and replaced the wheel with the bolt on the OTHER side of the spigot? Now it won't open AT ALL and the only way you can turn it is CW, but it is already closed. Either you break the valve turning it CW or the bolt turning it CCW, because it was not put together in time.

The clockspring might have a total of 5 or 6 revolutions that it is designed for, most vehicles only turn 2-2.25 CW/CCW off center, so about 4-4.5 TOTAL. If the clockspring is off 1 turn either way, or the vehicle is, it will be broken on the first full-lock turn.

 

Yup, something's not right in your installation. I replaced my clockspring a while back and it cured my problems. You'll have to take apart your steering wheel again and investigate. It's likely just a loose connection that wasn't properly seated. I remember several parts needing to click just right into place and it would be easy enough miss one. Also, there's a ground wire that's separate from the clockspring that needs to be connected.

If the clockspring is fully broken, I believe a warning light will turn on in the car, as the computer will detect that the steering wheel airbag is disconnected.

My $13 ebay clockspring is still going strong after more than 6 months!

 

I had an interesting day today. A few months ago I ordered, off eBay, two Clockspring assemblies for about $9 each. Since my speed control finally died, I felt it was time to do the install. Everything went well until the installation of the new part.

This is a warning to all. If you look at the picture you'll see a yellow plug. Somehow when I removed the plug I deformed it a wee bit. When I reinstalled the plug on the new part, as I pushed the plug into the socket it would not lock. I removed the plug and the clockspring to inspect for a problem.

Peering into the clockspring I saw two pins were deformed and pushed down. That happened as I attempted to mate the plug and socket together. It took about 1/2 hour to straighten the pins with some fine needle nose pliers. Once that was done I could gingerly reinsert the plug into the socket. The plug locked.

One other little change I did from the normal procedure writeups is that I did NOT remove the starting battery voltage at the back of the car. Everything was plug and chug and went smoothly.

 

I would not take this as a recommendation or see it as good advice. The primary reason to disconnect the 12 V is to dis-arm the SRS airbag in the steering wheel. While the chances of it going off inadvertently is maybe low, it is still a risk to be mitigated.

Do not do this repair without disconnecting the 12 V battery. You do not want the airbag exploding into your face.

 

Humm... I've heard that you MUST remove the 12 VDC supply to the car before you remove any SRS Airbags. So, I thought, before I started the project I'd look into this a little more. For me, half the fun is researching the project.

I came across this site that talks about the Gen 2 Airbag, and how it works: EE Times: Inside the Toyota Prius: Part 1 - The airbag control module

After reading over the information a few times I consulted the FSM. It seems that when the ignition is off and I've waited the 20 seconds for the caps to bleed down, then the car's SRS system is inactive. I see no ability to trigger the airbag.

Yes, the airbag could deploy due to a static discharge, but that could happen even if you disconnected the 12 VDC auxiliary battery.

Yep, I took an educated chance and lived. I'll likely take a lot of heat over this! ;(

 

Note: instead of disconnecting the battery, there is a fuse that can be removed to turn off any chance of power to the airbag circuits. I don't remember exactly which one, but if you look at Prius' wiring diagram it's fairly obvious (well if you're an electrical engineer like me...). This is another option for those who don't want to loose ECU settings (for me it's mostly to avoid having to turn off the reverse beep and passenger seat-belt beep).