I have a code P2101 (which is a Throttle Actuator Control Motor code) on my 2005 GMC Canyon pickup, and the repair manual does not tell me how to repair this so called "Throttle Actuator Control Motor, or where it is located at. Can you help me fix this? I had just replaced the throttle pedal, in hope that it was that, but no luck. I can sure use some advice on how to fix this problem. Please, can you assist?
2005 GMC Canyon 5 cylinder
I have replaced the gas pedal, or thottle pedal that the repair manual suggested. It has a actuator on the pedal itself, according to the repair manual, which cost me $67.00! But that was not the solution. problem still exist...no power, irregular or erractic idling, engine service light still on, and the scanner still displays error code P2101 Throttle Actuaor Control Motor. What do I need to do to fix this?
Welcome Razinman. The Throttle Actuator is the motor assembly that houses the motor to drive the throttle plates. The diagnosis of this code requires viewing data on a scan tool. The possible causes of this code are damaged wiring that is shorted to power or ground between the engine computer and the throttle assembly, the throttle assembly or the Engine computer (ECM) itself. The first thing I would check is the wiring and terminals from the ECM to the throttle assembly.
GM Grand Master Technician 2007. 11 years experience.
I thank you for the quick reponse! I will check out the wiring and see what I can find. If nothing is found, I will get back to you.
Your answer to my question was to look for a short between the ECM and the Throttle body . Well, so far I have not been able to fix the problem. What I did find
is there is a short that seems to exist or affect the left side tail lights. There is only the signal that works on the left side (drivers side), and no brake lights. All lights work ok on the passenger side, stop or brake, signal, and flashers or emergency. Obviously, there is a short somewhere. I could not say if your answer is the solution to my original problem, that is the P2101 error. I am still looking for the short, and it may take awhile. Which brings me to this question....why would the tailslights not work only on the drivers side, and everything is o.k. on the passenger side? Your answer to look for a short between the ECM and the throttle body affect the tail light operation only on the drivers side? Or does a short affect the whole or any part of the truck's operation, including tail-lights and engine?
The tail light has not connection to the P2101. These vehicles have had issues with the circuit boards for the tail lamps. There was even a recall on them. I would remove the left rear light socket and carefully inspect the terminals of the bulbs and the terminals and plastic surrounding the bulb terminals. Let me know what you find.
Jimmy Kurnosoff here. Back to the original problem......I check the wiring from the valve body, and it checks out O.K., but the wiring leads to a componant being called the "Powertrain Control Module" or the PCM. Is the PCM the same as the ECM, (Electronic Control Module)? And if the wiring is O.K., what would be my next vocus point search area that would cause the P2101 error code? ( Throttle Actuator Motor rng check)
I looked in the book for the location of a ECM, but there is no reference of a ECM.
Thatr is why I ask if the PCM & ECM the same? I really do not know and need some help here.
Yes, the ECM is the PCM. I think your next focus point should be the throttle assembly. I would want to do some more testing. Do you have a test light? I had a momentary mental block and for some reason thought you had an Envoy and not a Canyon so there was never a recall, However I would still pay close attention to the bulbs and the sockets. Also, do you drive on gravel? Sorry for any confusion and thanks for accepting. GM Tech39787.5719982986
I appreciate the correction on the recall, and for clearifying the the PCM & ECM. I was going nuts trying to find a ECM! Thank You! I will poke around the throttle assembly per your suggestion and see what can dig up. But it is a coincidence
for you to mention gravel......I have a gravel driveway, and so do others for I am in a country enviorment where gravel is common, and I think I see where you are going with it. So I'll check out a few things and let you know....O.K.? This may take a some time to check, but I will get back to you, and give a feedback upon completion of the problem.
Does your truck have a hitch?
yes,. it has a 4 link connection. I was planning to diconnect the wiring for the trailer and see if that would cure the taillight problem. But my main problem is the irregular idling and power loss issue. I cannot even drive it due to this throttle actuator motor error which the scanner is displaying code P2101. I was just wondering if the taillight short would cause the error, but according to you answer, it does not. So I still need to focus on the throttle assembly itself like you suggested. and my gut feeling is something with the throttle assembly, just as you said. so for now, I will focus on that area, and hope something there is the problem. I will get back to you with the results. I just need some time to check it out. Thank you for your suggestions, for at least I know where to look. sign, Jimmy Kurnosoff
Ok. Lets concentrate on the engine for now. Do you have a multimeter?
yes, I do have a digital mutimeter, and a auto-scanner plus.
ok, what we will do is check the wiring between the PCM and the throttle. If it is good, is suspect you need the throttle assembly. Start by disconnecting the ECM connectors and the throttle connector. Would you rather I send a schematic or written instructions?
yes! That would help out greatly! But you should know that I took off the throttle body assembly off just now. So I have it here on the desk.
That makes no difference. Here is the diagnostic chart with the steps for testing. We will have to start at step 5 as you have the code on. Here is the schematic for the throttle and HERE . Finally, HERE is the connector end views the the PCM. Please ask if you need some guidance through these. Also, be careful what you use to probe the connectors. They can be damaged easily. I recommend a sewing needle or something small that won' stretch the connector terminals.
Yes! I will need some, no, alot of guidance through this. I apologize for not being more savy minded on this. So I will take any assistance you are willing to give, and put up with my ignorance. But as I skimmed through the provided material, it would seem that I would need a test light, is this correct? If I do, I will need to take a ride to autozone and pick one up. Unless a digital multimeter would suffice. Do I need a test light?
A light will be needed. The multimeter is great for measuring voltage and resistance, but the light will be needed to verify the circuit can handle some amperage.
O.K. I will go and get one and get back to you. In the mean time I will accept the answer. But please be available in about an hour. Thank You!
Have you got a test light yet? The next couple of hours I will be online solid.
Yes, got the test light, I'm sorry for the time delay. Now where should I start?
I still have the throttle body on my desk. Should I reinstall it now or does it matter?
No, leave it off for now. give me 5 mins to form a plan.
O.K I'll be here. I am not sure how this site works , Do I accept each reponse, or do I accept the answer later after our completion on this matter? If you can help me out to get this truck runing39789.2083984144
Ok. First, connect your test light to ground and test that it works by touching the positive of the battery. If it lights up, touch it to the small metal tabs at on the op of the ETC fuse in location 20 in the under hood fuse block. Test it with the key on, and the key off. Let me know. You only need to accept once. Every Time you accept, I get paid and you get billed. You have accepted 3 times, that means you will be billed 45. If you wish I will request a refund of 2 of the accepts as I only expect one accept.
I 'll be right back
O.K. here is what I got. On #21 fuse link with the key off there is juice in one of the pins, specifically, the pin that is closest to the headlight shows power with the key on or off . no difference.
Need fuse 20, The fuse is labeled ETC
My mistake, be right back! and no do not request a refund. I am learning something here and it's worth it if we can get the truck running right again. Oh, by the way, it takes me a little time to get to the truck and back to the computer. the truck is in the shop way in back and it takes a couple of minutes to go there and back, so please be patient. I'll be right back!
I am not sure if my last answer got through, but herfe is a repeat: the pin closest to the firewall shows power only with the key on. Key off, nothing.
I have received all you replies. Try to move the throttle plates in the throttle body. Does the throttle return to the same position if you try to move it either way? It should be spring loaded.
Yes. the throttle plate works fine. all is good here.
Ok, next, with your test light on ground touch the end to the yellow and then brown. You will need the ignition on. the test light should flash momentarily, but not stay on.
Did I miss something? The yellow and brown what? where?
Sorry, this is at the connector for the throttle body on the engine.
Greetings and good morning!
Apparently we got cut off for I recieved a message that the site will continue this morning, so here I am, and in hope you have time and are here also. Are you there to pick up where we left off? You asked me to check the yellow & brown wires, well this is what I come up with......positioning the connector to where the yellow wire is at the top left with the connector facing me, and with the key on, there is only 2 places with power, counting from the yellow wire on the left, and counting to the right, the 3rd wire has power, and on the bottom row from the left is the 2nd pin or wire that has power, no other wires have any power to them,
including the yellow wire, which has no power.
I will be available at 1:00 mountain time, 30 mins from this message to continue assisting you.
Great! I will be here! and Thank You for responding!
Ok, the 2 wires that had power are 5 volt reference, that is good. Next Connect the clip of your test light the battery positive. Touch the light to the Yellow as you had it positioned before, in the top left, the upper left and the one to the immediate right of that. Only test on those 2 wires. HERE is a picture with the 2 circled.
Have you got any results?
I am sorry but I just got your message. I will be right back with the results.
O. K. here is what I got. with the diagram displayed, the pin on the left has power, whereas the one on the right does not.
They were the brown and yellow wires. You tested these again, but this time with the clip of the test light on the battery positive?
I stand corrected, they both have no power.
I double checked according to the diagram and with the clip on the positve battery terminal, there is no power shown on either one.
Perfect. Ok. On those 2 wires, yellow and brown. Connect the test light back to ground, and with the ignition off, hold the light to the yellow wire, and turn the ignition on. The light should turn on and then go off. Repeat the same with the brown wire. The last picture was rotated 180 from your description. It is the wire colours that matter.
O K, here is what I got. With the clip back on ground, and the ignition off, I connected the probe to the yellow wire and turned on the ignition, and nothing happened as you stated, it should go on then off, well it did not. I repeated this on the next wire to the yellow with the same result...nothing happened. I did this twice to be sure, and got the same result on both wires.
Ok. This next one is complicated. Remove the connector for the PCM. the one you want is a 56 terminal Blue connector. using a small piece of wire connect on end to ground and then using the other end and a pin or small probe device, put it into the terminal 38. I will have a picture HERE with 38 circled in blue, then using your test light with the clip on ground, touch the probe to the terminal 13, which I have circled in red. Be careful what you stick on these terminals, you can damage them easily. What you are doing when you put a ground to terminal 38 is turning on a relay, then that powers up terminal 13. This is the power feed for the throttle body. Let me know what you find. We are nearing the end of the diagnosis.
O.K. This will take a few minutes for the result. Please do not go anywhere! I will be right back after I do this test. Just so you know, I have deposited some more cash for you which I will send upon completion of this testing and we get the truck running again. Be right back!
Question....there are 3 main connectors to the PCM, could you direct me to the connector of which I am to focus on? and perform this test ? Left, the one closest to the fender, center or the right , one closest to the engine?
It is not the large center connector. With out looking I cannot tell you if it is closer to the engine. The connector you want is blue, or has a blue seal, not grey. Does this help?
Yes! the blue one, in my case, is the one closest to the fender. I'll be right back with the results.
I have only another 20 mins, then I will be offline for a few hours. My kids have their Christmas program at Church.
O.K. now I connected a wire from the terminal or pin 38 according to your diagram to ground, with a small pin, then I connected the clip to a ground of the test light, and then with the key still off, I touched the terminal or pin 13, which is at the bottom row 2nd from the right with the test light probe, and got nothing, when I connected the ground wire to pin 38, I heard something clicking on. I would guess this is what we want. I doubled checked your instructions and my connections, and still got nothing with the test light.
Ok. The test light should have illuminated when you connected the ground to terminal 38 and had the test light on the 13. This leads me to think you have a wiring issue between the fuse block and this wire at terminal 13. Just to confirm, you did put the ETC fuse back in and it was good?
No it was not in, but I put it back in and now it does go on! I am sorry, my bad.
No problem. Hook the PCM back up and repeat the test where you put the test light on the yellow and turned the key on. Repeat with the brown. If both turn on then go out after you turn the key on, then you need a new throttle assembly. The light may flash on and off rather than turn on and off. I have to go offline now. Leave the results and I will reply later this evening.
Understood. I will do that and give you the results and look foward to talking to you tonight. Can you give me a about time you will be back online?
I hope around 8:00. mountain, so about 3 1/2 hours from now. Talk to you then.
O.K. so until then.
Thank you again. Did you get the test results?
Yes. I put together the PCM and tested the yellow wire and it did flash on then off, then I tested the brown wire, to the right of the yellow wire, and it did the same. But, when I went back to test the yellow wire again.....nothing! Same with the brown wire, nothing! Why is this? I double checked it again, from yellow, and then the brown and nothing! What happened?
I think that is because of the PCM seeing that there is a fault. I would not worry about it. You only needed to test it once. I expect that if you go and test it now that it has been sitting for some time, it would work again. Either way, the fact that both wires did light the light for a moment shows the PCM is working. The next step is to check the connections and you have done that so that leaves the throttle body.
Is there a way to check the Throttle Body ? Like somehow connecting something to it to see if the plate opens up ?
No, the tests I had you go through are the tests from the diagnostic chart. Basically we checked everything else except looking at the Throttle position sensor data in the PCM, but without a GM scan tool or equivalent, we could not do that. Even though we could not do that test, the results gave us 2 choices, first, there is no fault, and we know that was not the case or start with the other diagnosis. We checked that the PCM is sending power on both lines, checked that the wires, brown and yellow are not shorted to power or ground. The PCM alternates power and ground through those 2 wires to control the throttle. Based on everything, the throttle assembly is the last thing.
So, at this point, would you recommend getting another Throttle Body?
You have not replace the throttle body did you? I was under the understanding that you replaced the throttle pedal sensor, not the throttle body on the engine?
Yes, that is correct,. I did not replace the throttle body, but did get a new throttle pedal, so that leaves the throttle body itself that may be bad?????
Based on all the tests we have completed and the results, I would replace the throttle body if this was my truck or I was working on it.
Understood. Well, that is what it leads to, so O.K. I will order one and after I install it, hopefully that the truck will run. If you would like, I can give you the result in a couple of days after I install the throttle body. Would that be O.K.?
Absolutely. I want to hear that your truck is running properly and our hard work was worth it. I checked quickly, and there is nothing special about the replacement of the throttle assembly. No special calibrations or setup needed.
Great! You know through all this work and communicating, I did not catch you name, care to disclose it? I am Jimmy Kurnosoff and I am in Kerman California. Where are you? And I want to Thank You XXXXX for your time and effort in helping me with this problem. Your instructions and patience are outstanding to say the least! I learned something here that is definately worth the time! And I will get back and let you know the results. Again Thank You!
My name isXXXXX live in Alberta, Canada. I cannot tel you any more or I will get in trouble for disclosing personal information. It has been a pleasure assisting you.
Have you had any luck?
No, not yet. I am still waiting for the throttle body housing, which should be in on 12-16-08. I hyad ordered it on 12/08/08, but due to bad weather, it was delayed
until the 16th. So, I have no choice but to wait. But, as soon as I get it and install it, I will definately get back to you, for I may need more assistance, but for now, it's the waiting game.
until the 16th. So, I have no choice but to wait. But, as soon as I get it and install it, I will definately get back to you, for I may need more assistance, but for now, it's the waiting game. I
until the 16th. So, I have no choice but to wait. But, as soon as I get it and install it, I will definately get back to you, for I may need more assistance, but for now, it's the waiting game. I will post a feedback at that time...O.K.?
OK. Thanks for the update.
Thank You for your interest. It shows me you are a pro, and a man of his word.
So until the 16th, have a good weekend.
<emCustomerHere again! We left off with me getting the Throttle Body Housing" as per your suggestion and installing it, and after walking me through the diagnostics, (which was a little tricky) I am happy to report the results of all the work put into this project was worth it, to say the the least.! It seems to run better than it did before the problem started! My hats offs to you. Thank You Very Much for the expert advice and your patience working with me, with your detailed step by step direction, it couldn't be any better! Not only did I get the truck running, I got the running better than before, and I learned a thing or two
on my truck, that I can use for future reference. Again, I Thank You for all of
your assistance in this matter. You can bet I will recommend this site if I hear of somebody who may be in need! Sincerely, XXXXX@XXXXXX.XXX