So, back again with another issue!

Finally got the other issue resolved by having my cat replaced. During the time at the shop, somehow some way, my power steering stopped working....

I checked with the Lexus dealer, and all recalls have been done. Doing some research, I figured I'd get another Steering ecu. Did that, replaced it, and still nothing. I did notice that the actual connector that leads down to the rack was cracked and wouldn't seat fully so I sort of Jimmy rigged it tightly with zip ties just to see what would happen, and nothing. Also read online that the 4 pin connector sometimes is the issue. I cleaned them, re-seated all connectors, and I got nothing. Cleaned grounds, nothing. I did check all the fuses (even the ones that have nothing to do with EPS), swapped relays for the EPS, and I got nothing. There is power going to the unit.

I'm trying to exhaust all options before I break down and take it to the dealer for a diagnostic and potential bad news. Any input? And by the way, everything else works just fine electrically. Just the P/S light on the dash.

Do I need to possibly have it recalibrated? What say you with this issue?

 

I wish you hadnt replaced the steering ecu so fast, because now we dont know what the current issue is, if it was the connection to the rack or the calibration, that could be fixed. Or because you replaced the ecu and it needs a recalibration. I would try the recalibration if you are able to do it yourself.

Also did you check the battery terminals? Maybe the shop removed the battery terminal and broke a terminal internally, because ive had a weak battery terminal kill my power steering once. Did you call the shop and ask what happened? Maybe they arced something or left a ground loose?

 

Iirc, Techstream is required to do the calibration, right? Unfortunately, I don't have access to that unless someone can point me in the direction of obtaining that, or if its not required, how to do the calibration in general.

I checked the terminals to the battery and cleaned them. When you say internally, do you mean a mean a pin to the EPS unit?

I asked them what happened, and was told that they never messed with the unit itself. They did unhook the battery though, and when they were done, they test drove it, parked it and called me for pick up. When I got there, I saw the P/S light on.

Are there any grounds near the cat on the passenger side that I should look for?

 

The stock battery terminals are thin metal so after time they can break easily internally and not provide a good clamping force on the battery. Remove the battery terminal and inspect it make sure its clean and not broken inside.

 

Ahhhh okay okay. I will check and probably replace just for good measure.

 

Hey, so I had the codes pulled today and they are

C1512 and C1513

The tech says that there isn't any power getting to the rack, and he replaced something on the rack (can't quite remember what it was) and it still didn't work.

 

If the rack isnt getting power did he test the power module to see if its getting power aswell or did he just take a guess that its bad? Did he preform the steering angle sensor calibration?

 

Power is getting to the module itself. He also mentioned that the EPS relay isn't coming on... Ermmm, he didn't say if he did or didn't attempt. I assume he did not... he wants to trace the problem down to an electrical wiring issue.

 

Correction: C1511 and C1555
He is now suggesting that I replace the steering rack.

 

Is this a lexus dealer? Why replace the rack if the module is not getting any power? Did he try and track the power supply to the module?

 

No, this is someone that was recommended to me by a family member. I haven't had too many good experiences with the Lexus dealer here in South Atlanta. But, the EPS module itself is getting power. It's anything after that, down the harness to the rack that isn't getting power.

 

Take it to a lexus or even toyota dealer, I just feel this mechanic is not familiar with diagnosing lexus. Pay for 1 hours of diag, and have this mechanic do the repair. If you need to replace the rack you can buy a used one at closes junkyard near you. www.car-parts.com is a great search to find the rack

 

So, I went back up there to pick the car up, and he showed me a loose wire. Well, one that came all the way out. HOPEFULLY that is the cause of all of this. It was a green and white wire in the connector that leads to the rack. I ended up purchasing another harness to have him put in. If this does not correct the issue, I will definitely take the car to a dealer. But for some odd reason, when I called one of the local Toyota dealers, they informed me that they only do basic maintenance on Lexus models.... I find this hard to believe...

I got an Auto Repair subscription that shows me everything related to the car, and apparently, that particular wire does lead to the Torque Sensor (pin 9 on the C4 Connector), which is why I could only assume I'm getting the C1511. The C1555, I'm still at a loss there though, personally. Unless, since the grn/wht wire is out, it cuts all power to the rack motor, thus throwing the C1555?

 

This technician couldn't find a way to connect the wire into it's correct port as soon as he found it, so he would know if replacing the harness would fix the main issue? Or if this broken plug is just part of the solution? Usually u can pull the wire and terminal out of a broken plug and stick the pin into the right socket really easily, and find out where he was going to be at after replacing the harness. If it still has problems, it's better to know so the diagnostics can continue til resolved and he isn't keeping the car outta service for any longer than necessary?

 

I agree, that should've been the method taken in order to continue diagnosing the possible issue I was having. Good thing is, the connector lock was already brittle/broken so it was a good idea to replace the entire thing anyway, at least for me just for reassurance that the entire harness would be intact. But the update is, that clearly that was the issue (steering works once more). Sad thing is, he is charging me $600 for diagnostics and labor. A bit of a rip off yes, but at least its working again. And its miles cheaper than what the dealer quoted me to do the same.