Codes P1516 & P2101
Thread Starter
3rd Gear
Joined: Aug 2011
Posts: 3
Likes: 0
Codes P1516 & P2101
I have been trying to locate the TAC module for my 2005 Corvette. I am getting codes P1516 and P2101, which could mean the TAC module. I have researched in your forum and others, but when I go to try to find the part, I get different answers back from the parts places, including GMPARTSDIRECT. They actually gave me a Transmission Control Part #. I understand from my research that it could be called an Electronic Throttle Control, but when I checked for that they couldn't find it under that name. I also got back something called an Emission Control System Hardware, but it has a core charge and from my understanding there should not be a core charge so I'm thinking that's not the right part either. I have been searching for hours! Can anyone help me find the right part number for this? Also, can you tell me how many connectors are on this module?
Thanks,
Thanks,
Instructor
Joined: Jun 2011
Posts: 238
Likes: 1
From: Clayton North Carolina
P1516: throttle actuator control (TAC) module.
P2101: Drive-by-wire relay control circuit.
BTW, is the car running in limp mode along with these codes?
Found these on a forum search here.
Another search on the web noted: check throttle body for excessive carbon buildup as well as relearn idle; "disconnect battery for a while, hook back up and start car. Let vehicle run 5 minutes and turn off. Let car set 10 minutes and then start back up and run for 5 more minutes.
Then road test.
Let us know what happens.
P2101: Drive-by-wire relay control circuit.
BTW, is the car running in limp mode along with these codes?
Found these on a forum search here.
Another search on the web noted: check throttle body for excessive carbon buildup as well as relearn idle; "disconnect battery for a while, hook back up and start car. Let vehicle run 5 minutes and turn off. Let car set 10 minutes and then start back up and run for 5 more minutes.
Then road test.
Let us know what happens.
Thread Starter
3rd Gear
Joined: Aug 2011
Posts: 3
Likes: 0
P1516 and P2101
Thank you for answering so quick. I've been working on this for several days. Yes it does go into "limp mode" and then I let it sit for a minute, start it up, and all is well for 17 miles. If I let it sit for a day or two, I will get 17 miles before it does it again in one trip. I can make short jaunts and it won't do it. I live in Wisconsin so I only use it in the summer. I don't believe there is carbon buildup, but I will do as you say. I'm trying to work with my Auto Repair guy and am trying to order the part for the TAC module, but keep getting different parts. Now I got the throttle body part number. He put it on diagnostics and the first thing that came up as a possible problem was water so he checked and there was some calcification buildup, but it was not wet. It happened after I had it washed at a brushless carwash, but they have an underbody flush that starts when you first enter, but I have been having it washed there since I bought it in 2005. This just happened this year.
I will get back to you after I try this. Thanks again!
I will get back to you after I try this. Thanks again!
Race Director
Joined: Mar 2010
Posts: 16,002
Likes: 824
Sorry to hear that you're experiencing similar concerns. I would be happy to communicate this situation with the designated Customer Experience Manager at your preferred dealer if you feel an official diagnosis is necessary. Feel free to message us privately if you'd like to proceed, or discuss this situation further.
William R.
Chevrolet Customer Care
Tech Contributor
Joined: Oct 1999
Posts: 41,044
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From: Charlotte, NC (formerly Endicott, NY)
Bill
Intermediate
Joined: Nov 2012
Posts: 28
Likes: 2
From: Virginia Beach Virginia
Not sure I see a clear fix here. I have a stock 2009 that's been intermittently throwing P1516 and P2101 with reduced power mode. The car will come out of reduced power mode after a couple of restarts, but the idle rpms drop lower than normal. Sounds like a new throttle body and gas pedal assembly are in order?
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3rd Gear
Joined: Nov 2018
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Today my 2006 c6 threw the P2101 code and went into limp mode for the second time in about 1000miles. After restarting it ran fine. Before I completely replace the throttle body have any of you had luck just doing a thorough tb cleaning and relearn routinely? Or is there a part of the throttle body that frequently goes bad requiring replacement?
Safety Car
Joined: May 2006
Posts: 3,693
Likes: 485
From: Potomac MD
I would also check the wiring at the connector make sure it is on snug at the TB. Pull connector off and make sure it goes on nice and firm. If really loose/sloppy you may need a new pigtail connector.
1st Gear
Joined: Oct 2024
Posts: 1
Likes: 0
Ok so new to the forum but having a similar issue. Car runs great for an hour then goes into limp mode and runs like crappe. Codes are p2101 and p1516. I can even clear them with a pocket code reader while driving and as long as i dont snp throttle it will run ok for 3 or 4 minutes then back into limp mode. I have checked all the wiring and connectors. I have disassembled and checked the entire throttle body and cleaed and reassembled. Installed new tps. Removed the tcam and checked pins and connectors. Reinstalled. Drove great all day in houston several times above 100mph. 7hrs into the day everything starts again. I have no issue buying and replacing or updating this sytem. It seems that all the parts available are used on ebay. Can the throttle control module be bypassed if i istall performance intake and larger throttle body? Or can someone direct me to where to find any quality part. Oh and i forgot to mention i am a master technician and i own multiple shops so im certain i have identified the problem i am just new to the c5 platform. Any help would be amazing
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,564
Likes: 4,034
From: Cape Coral, Florida
Ok so new to the forum but having a similar issue. Car runs great for an hour then goes into limp mode and runs like crappe. Codes are p2101 and p1516. I can even clear them with a pocket code reader while driving and as long as i dont snp throttle it will run ok for 3 or 4 minutes then back into limp mode. I have checked all the wiring and connectors. I have disassembled and checked the entire throttle body and cleaed and reassembled. Installed new tps. Removed the tcam and checked pins and connectors. Reinstalled. Drove great all day in houston several times above 100mph. 7hrs into the day everything starts again. I have no issue buying and replacing or updating this sytem. It seems that all the parts available are used on ebay. Can the throttle control module be bypassed if i istall performance intake and larger throttle body? Or can someone direct me to where to find any quality part. Oh and i forgot to mention i am a master technician and i own multiple shops so im certain i have identified the problem i am just new to the c5 platform. Any help would be amazing
I would start a new thread in the C5 Tech section as this was posted in the C6 section…if you have shops have you checked the code setting criteria for these 2 DTC’s and if you are not familiar with electrical troubleshooting you can use the OE flow charts…you don’t have a factory level scan tool to use instead of a “code reader” ??…do you have a lab scope as these ETC circuits are best observed using a scope ??…always a good idea to let us know what model year we are dealing with…is it a 2004 based on the P2101 ??
Last edited by C5 Diag; Oct 4, 2024 at 08:48 PM.
