Check engine Code P1126

[Micah]

I need to get emissions done this week and it won't pass with a check engine light on. I got the same code from two places so feel certain that it reading correctly. Ive used the search function and couldn't find conclusive advice on if just the motor needs to be replaced or the whole throttle body?

Thanks in advance

 

[kev301]

With that code, there are three areas to check, 1) Check to see if there's an open or short in magnetic clutch circuit, 2) Check to see if the magnetic clutch is bad and 3) Check for open and short in harness and connector between magnetic clutch and ECM.

You can check the magnetic clutch by measuring the resistance between terminals 3 and 4 of the throttle control motor with the magnetic clutch.

Here's the diagnosis and repair from Mitchell OnDemand

 

[AimCOtaco]

I don't know if you can purchase the motor individually like you can for the APPS and TPS. The error is more likely the linkage/geartrain than the motor it'self.

I do know that after replacing the complete TB about 5 years ago I have had zero issues with that family of error codes.

 

[Micah]

I do know that after replacing the complete TB about 5 years ago I have had zero issues with that family of error codes.

So I understand getting new parts is always a good thing to do but exactly what would be the benefits for getting a new TB? (Other then getting rid of this code?

 

[AimCOtaco]

It could reduce incidence of problems as it replaces so many suspects; the APPS, TPS, Motor, clutch, gear train, bushings, and throttle butterfly.

If you have an actual gear train bind or failure a full TB would be the only real fix. Ours was my wifes daily driver when we bought it with about 170,000 miles on it and we were getting intermittent codes and limp mode in traffic. To me I was happy to put it all to bed and stop worrying about going into limp mode. Now that it is an extra/fun vechile I would consider the cheaper/harder path but you could still end up replacing the TB. Replacing the TB also leaves you with some spare parts for repairing/troubleshooting other 100's on the trail(assuming mine is now good for another 170k+).

 

[Micah]

AimCOtaco if you don't mind me asking what did you end up paying for the new TB? Did you get it through CDan?

 

[AimCOtaco]

Actually only paid 735 but that was in 2011 and the particular online retailer no longer sells toyota parts. Today I would say if you're under 1000 you're probably doing pretty good, they have gone up for sure.

 

[4wheelforay]

Micah, was your truck going into "limp home" mode when it was throwing that code?

I recently purchased a 98 LC, and on the coldest day of the year it started, shut off, started again with a little throttle input, and drove fine. Upon restart after reading the code at autozone it went into limp home mode. It is throwing P1126 code, and continues to operate in "limp home" mode. At this time I am unable to check resistance per the image shown above. Is it a gamble to replace the throttle control motor, could it be a bad harness or ECM?

Thanks for the help! It is much appreciated!

***EDIT***

Tried to add pics and deleted my update.

Loose connector at my throttle control motor was the culprit. I had the TB done 2 months ago and I guess it was disconnected and not seated when it was reconnected... maybe.

I went searching the internet for a replacement throttle control motor and realized that I may have been looking at the wrong connector, I popped the hood and the connector at the throttle control motor wasn't seated. I clicked it, cleared the code, and now the truck runs like it should.

It is the connector in the foreground (right side of the throttle body, when looking at the engine)

Throttle control Motor

• 4wheelforay
• Jan 15, 2016

 

[smileyboy]

Thanks for the post. My '99 LC threw a p1120 code about a month ago on the way back to Denver from Salt Lake City. I checked the code and cleared it. Then 2 weeks in a row I've gotten the P1126 code. I'm not sure if I should start with this part or not. Anyone have any ideas?

Maybe I'll start with the connectors

 

[Hoserock]

Thanks for the post. My '99 LC threw a p1120 code about a month ago on the way back to Denver from Salt Lake City. I checked the code and cleared it. Then 2 weeks in a row I've gotten the P1126 code. I'm not sure if I should start with this part or not. Anyone have any ideas?

Maybe I'll start with the connectors

 

[Hoserock]

Just got this code on my 00 LX with 174k, TB done 2 months ago. I tightened my throttle body cable as it had about an inch of play. Afterwards I noticed and immediate change in response. Then came the p1126 code. After reading this thread I disconnected the aforementioned connectors and it seemed to work!?... hopefully that takes care of that, thank you guys so much for this info.

 

[joshuatarr]

I recently got this same p1126 code. In the last 3 months I did do the alternator so I was unplugging and unhooking lots of these things. I attached and reattached the harness, which cleared it but it came back. Somewhere I read on here that using lower octane gas could be a culprit, and I had been putting in 85 for about a year, so I threw in a tank of premium and seems to have been resolved? Looks like the throttle body is backordered in alot of places right now so, hopefully this takes care of it...

 

[Sal DeVincenzo]

I need to get emissions done this week and it won't pass with a check engine light on. I got the same code from two places so feel certain that it reading correctly. Ive used the search function and couldn't find conclusive advice on if just the motor needs to be replaced or the whole throttle body?

Thanks in advance
View attachment 1141149 View attachment 1141150

An old thread, but I have this problem. Also, one thing I found that actually gets it to go away is a light tap on the throttle motor body.
Turn off the engine, give it a couple of light, gentle taps, check the electrical connectors disconnect the battery for a minute or so reconnect and start it up. If you're lucky the light goes out and stays out for a while morning there is a windings issue with the motor or a dirty Internet connection.

 

[Sal DeVincenzo]

An old thread, but I have this problem also. One thing I found that actually gets it to go away is a light tap on the throttle motor body.
Turn off the engine, give it a couple of light, gentle taps, check the electrical connectors disconnect the battery for a minute or so reconnect and start it up. If you're lucky the light goes out and stays out for a while morning there is a windings issue with the motor or a dirty Internet connection.

 

[Hoserock]

An old thread, but I have this problem. Also, one thing I found that actually gets it to go away is a light tap on the throttle motor body.
Turn off the engine, give it a couple of light, gentle taps, check the electrical connectors disconnect the battery for a minute or so reconnect and start it up. If you're lucky the light goes out and stays out for a while morning there is a windings issue with the motor or a dirty Internet connection.

Try a little dialectic grease in the connectors. I get the same code when its cold out, I clear the code and it's good to go.