C1513 Code Torque Sensor Issue

[myfootsmells]

Great now after shelling out $3300 for the transaxle, my dealership said while test driving the car another code came up, C1513 open circuit at torque sensor inside the electric steering rack and it'll cost another $3000 to replace.

What I don't get is why when it was at Key's Toyota no code came up. Then when I took it to Longo Toyota no code came up, but just as they finished the transaxle and took it for a test drive the code appears. Sounds kind of fishy to me??

Is there any chance that while replacing the transaxle they broke something regarding the steering?

Michael

[Bobwho]

Get the Bentley repair manual and do some heavy reading.

[myfootsmells]

I don't follow?

Originally Posted by Bobwho

Get the Bentley repair manual and do some heavy reading.

[ChapmanF]

Originally Posted by myfootsmells

Is there any chance that while replacing the transaxle they broke something regarding the steering?

The steering rack lives on the "engine cradle"/lower suspension support and it all had to be removed to get the tranny out. So the electrical connections to the steering torque sensor surely got unplugged, and the contacts after 6 years may have been a little grimy, or they could have gotten a little grimy in the shop, or not plugged back together quite right.

My local electronics shoppe stocks a spray-can chemical called Jiffy Bath, a contact cleaner that leaves a protective and lubricating film. I couldn't begin to list all the "dead" electronic devices that I've resurrected by taking apart all pluggable contacts, hitting them with Jiffy Bath, re-plugging/unplugging/re-plugging them a few times, and trying again.

The torque sensor depends on sensing a variable resistance, so getting an iffy connection at any of the plugs they had to disconnect would definitely give you grief.

I suppose it's also possible that they actually damaged the torque sensor inside the steering gear itself - but I would certainly try the contacts first.

There was a service campaign for a known issue where the torque sensors in steering gears with a certain range of serial numbers did go bad. I don't know if your gear is in that range. Even if that happened, if there seemed to be any way to disassemble it enough to reach the resistive elements inside, I would try hitting them with - you guessed it - Jiffy Bath. I very successfully repaired a dying intermittent-wiper-delay knob that worked on pretty much exactly the same principle and had gone bad the same way. But getting to the steering gear for anything beyond cleaning the plug-in connectors would probably require dropping out that lower suspension assembly again, which looks like a PITA (I've never done it yet).

You can get the Repair Manual and the Electrical Wiring Diagram in a couple of ways: 1. at techinfo.toyota.com by paying $10 for a day of access and downloading as much as you can through a really hellish web interface of buggy JavaScript, or 2. calling 800 622 2033 and ordering them as nice books.

Hope this helps!

-Chap

[tochatihu]

If a connection with the steering ECU is loose or corroded the above may certainly help. As far as improving the function of the potentiometers inside the torque sensing system, I have been 'in there' and they are not accessible without damaging during disassembly. Not an ideal serviceable design (understatment).

Unfortunately it is not uncommon for those potentiometers to partially fail in 2001-2002 Prius. So focus first on ChapmanF's idea. If you eventually determine that the steering has failed, (a) $3000 may not be the lowest dealer-installed price (b) Toyota's 'hot line' may be willing to negotiate cost sharing (c) the salvage dismantlers will sell you the entire power steering assembly from a crashed one (ideally, 2003 with rear only damage).

[myfootsmells]

working on (a) and (b) right now. any recommendations for (c) as far as a good salvage company to talk to?

thanks everyone.

michael

Originally Posted by tochatihu

If a connection with the steering ECU is loose or corroded the above may certainly help. As far as improving the function of the potentiometers inside the torque sensing system, I have been 'in there' and they are not accessible without damaging during disassembly. Not an ideal serviceable design (understatment).

Unfortunately it is not uncommon for those potentiometers to partially fail in 2001-2002 Prius. So focus first on ChapmanF's idea. If you eventually determine that the steering has failed, (a) $3000 may not be the lowest dealer-installed price (b) Toyota's 'hot line' may be willing to negotiate cost sharing (c) the salvage dismantlers will sell you the entire power steering assembly from a crashed one (ideally, 2003 with rear only damage).

[tochatihu]

I dunno who is good. LKQ online puts the most Prius stuff up on ebay (often including steering assemblies). Google their competitors (as if you didn't know how...). In the ideal case, more than one is available, and the merchants would compete in terms of price, shipping and warranty term (if any?). Seems like the ebay price is about $500.

It might be tricky to get that installed, if the Toyota shops say no. I reckon Art's in Berkeley would do it, but that's a road trip north.

For now I'd rather work on the assumption that it's fixable along the lines of Chap's ideas. Good luck.

[ChapmanF]

Originally Posted by tochatihu

For now I'd rather work on the assumption that it's fixable along the lines of Chap's ideas. Good luck.

Look also in the Repair Manual for a procedure to reset the steering ECU's idea of where "zero" is on the torque sensor. Even if nothing else happened, an electrical connection that was undisturbed for 6 years, then unplugged and reconnected, probably has changed the circuit resistance a bit and would make that calibration necessary.

And the manual has some tests you could do with a voltmeter if the simple plug-cleaning doesn't do the trick.

The recalibration procedure can be done either with a Toyota Hand-Held Tester (easy but only practical if you have one, which probably means you're a dealer), or without one, by a carefully executed sequence of shorting pins 13 to 4 and 14 to 4 on the diagnostic connector while watching a blinkenlight (which you have to supply, connecting it between a ground and pin 7 of the 10-pin connector on the ECU). I won't even try to repeat the details from the manual - there are a lot of them, and you'll want to follow them very attentively.

Almost all the other ECUs can tell you things (without the Toyota scan tool) by blinking some existing light on the instrument panel when you activate a test mode; for some reason the steering ECU is the one where you have to hook up your own light before you can look at blink codes.

-Chap