P1121 code, tried a few things but nothing! Help!
#16
Sounds like the throttle body is bad. (cheaper to buy a used complete 1 than to try
different sensors) You can try & clean the throttle body - worth a shot. Disconnect
the battery 1st, do not spray inside it (spray a rag or tooth brush) & DO prop the plate
open w/ a wood/ plastic tool handle. The throttle plate is on a geared motor & WILL
bite you.
The cable going to the throttle body is for limp home only - so your not stranded in the
middle of the road. Newer versions of fly by wire have deleted that cable all together.
different sensors) You can try & clean the throttle body - worth a shot. Disconnect
the battery 1st, do not spray inside it (spray a rag or tooth brush) & DO prop the plate
open w/ a wood/ plastic tool handle. The throttle plate is on a geared motor & WILL
bite you.
The cable going to the throttle body is for limp home only - so your not stranded in the
middle of the road. Newer versions of fly by wire have deleted that cable all together.
#17
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Glad to see a recent post on this. I'm having the same issue on the GFs 2001 is300. It happened all of a sudden when she was trying to pass on a hill, car lost all power. I scanned the car initially and got P1120, P1121, P0171, and P0174. I took the car out and drove it and it was definitely stumbling, and surging on / off when trying to accelerate. I cleared the codes and drove around a little more. It took a while and a few warm up cycles before I could duplicate the issue again. The second time, I only got the p1121 code, so I'm leaning more towards the accelerator pedal position sensor. Is there a difference between the throttle position sensor and the accelerator pedal position sensor from those pdfs? I'm thinking about just replacing the sensor really quick.
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Where is the accelerator position sensor located at? Is it the one closest to the actual TB and wire? I'll look into used throttle bodies and see what I can find on ebay. I saw the video and checked everything on the car which seemed normal. It was snapping back when opening the throttle 100% and I didnt hear grinding or friction. in the pdfs attached telling the steps to check the voltage (p1120 I think) where is that box located? I pulled off the lower instrument panel under the steering wheel and wasn't sure where it was. I saw a box with a lot of wires in it but it wasnt exactly that same as the diagram.
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Where is the accelerator position sensor located at? Is it the one closest to the actual TB and wire? I'll look into used throttle bodies and see what I can find on ebay. I saw the video and checked everything on the car which seemed normal. It was snapping back when opening the throttle 100% and I didnt hear grinding or friction. in the pdfs attached telling the steps to check the voltage (p1120 I think) where is that box located? I pulled off the lower instrument panel under the steering wheel and wasn't sure where it was. I saw a box with a lot of wires in it but it wasnt exactly that same as the diagram.
As for the box they speak of on the PDF, that's the ECM (ECU) located on the passenger side underneath the carpet (atleast on the SC300 it's there). You should check all the voltages on the sensor PINs before checking the ECM though (VPA, VPA2). Thats the way the manual says the troubleshoot.
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The accelerator position sensor is this one, closest to the firewall:
As for the box they speak of on the PDF, that's the ECM (ECU) located on the passenger side underneath the carpet (atleast on the SC300 it's there). You should check all the voltages on the sensor PINs before checking the ECM though (VPA, VPA2). Thats the way the manual says the troubleshoot.
As for the box they speak of on the PDF, that's the ECM (ECU) located on the passenger side underneath the carpet (atleast on the SC300 it's there). You should check all the voltages on the sensor PINs before checking the ECM though (VPA, VPA2). Thats the way the manual says the troubleshoot.
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TJ were you having the same issues with power loss? I already bought the TB with the APPS and motor, and was planning on reusing the stock TPS thats on the car now and hope that eliminates the problem. MD have you solved the issue with the other TB?
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So I made an attempt to remove the Throttle Control Motor with no luck. As you can see from the picture below, I was able to remove the top screw but the two bottom screws are stubborn as hell!!! I used a great screwdriver too and nothing, they both ended up getting stripped! I'm so pissed, I think I would be better off just replacing the whole TB. Anyway, it's dark now, I think tomorrow I'll try replacing the APPS instead since that seems a little easier to do. If that fixes my problem then I dont have to worry about the motor, if not, I guess I'll have to come up with something to remove those two screws.
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So I successfully replaced the Accelerator Pedal Position Sensor and drove the car around for about 40 minutes and NO engine light and NO limp mode so it may have been the APPS that was bad. I'm going to keep on driving it and hopefully it doesn't come back. I'm so glad I didnt have to replace the Throttle Control Motor because I dont know how I was going to remove those stubborn screws.
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Been driving the car for a week and nothing so the APPS fixed the issue. Just wanted to let everyone know that if you ever suffer the same symptoms it is most probably the APPS.
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Thanks for the update. So far I got the used TB from ebay but I'm pretty sure I got a bad one. I'm still throwing the code but its even worse after installing the ebay TB. As soo as I tried to start the car it revved up to almost 4k rpm and wouldnt idle steady at all. I adjusted the TPS but could only get it to keep idel at about 2k rpm. Then I started throwing the P0120 and P1120 code like neither the APPS or TCM were working. Any suggestions? I'm checking local junk yards for the part and have a new TPS from autozone here. I'm pretty sure its the APPS, not the TCM as MD99 was having the same issues. Anythine else I should try? Does it sound like I'm doing thinks right? Thanks
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Well we did a combination of things trying a new TPS from autozone, then trying to make one good part from the 2 throttle bodies and nothing worked. Even with the TPS at the lowest CW position it still reved at 2k rpm at idle. Of course if I adjusted it CCW it would rev even higher because it was opening the throttle body. I contacted the seller from ebay and he is sending me another complete TB with the APPS, TCM and TPS on it and it has been tested and off a working car. I'm going to try again this weekend when I get the part. One thing I did notice which seemed odd was the voltages across the different sensors. With the key in the on posisition I was reading 5v reference from the ECU on the APPS and TPS, but only 1V reference for the TCM. Does this seems right? Most of the time its always a 5v power but I'm not sure on this car. If this new TB doesnt work I'll be hunting down a short somewhere in the wiring which I hate doing.