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Tac module problem

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Old Apr 10, 2025 | 08:33 PM
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Default Tac module problem

Hi I'm pretty new here I've had the car for 4yrs now and I'm running into some trouble. My tac module went out a year ago and I just now got around to getting another one. My car has a manual trans and I put an tac from an auto car in it and I'm getting 3 codes p1515, p1221, p0108 I was hoping to get some help. Thank you in advance I would really appreciate it.
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Old Apr 11, 2025 | 01:10 AM
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Moved to C5 Tech.
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Old Apr 11, 2025 | 02:47 AM
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Here are what those codes mean.

P0108 Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage
P1515 Control Module Throttle Actuator Position Performance
P1221 Throttle Position (TP) Sensor 1‐ 2 Correlation

I am not 100% sure on this, it would seem that the throttle body Actuator may be bad or wiring to it is damaged.
Your original TAC module is probably good. If the information I have is correct, the TAC module does not care if it is an auto or manual car.

I had a friends car that had issues going into limp mode. While inspecting the car I found that someone had spliced the harness for the throttle pedal to TAC module doing a very bad job of it. I had to run a new cable for it and splice the connectors back in. After this it worked for about a year, ended up swapping the TAC and have no reported issues since.

Gary
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Old Apr 11, 2025 | 10:47 PM
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Default Thank you !

I appreciate your help. I will look into it and get back with you as soon as I find something. I was worried I just bought the wrong module. I took the old one apart it did have some water in it and it looked like someone was in it before because the lid was cracked and had silicone on it.
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Old Apr 18, 2025 | 11:27 PM
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I ran a meter on all the wire there good. Pulled the intake off and found my map sensor was broken. Could that possibly be making the tac to not work properly
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Old Apr 19, 2025 | 10:32 PM
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That may have some bearing on your issue. I don't recall completely but the 5v reference for the MAP may also be used by the TAC module. If so this will cause various errors.

Gary
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