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I have code p1518 pcm to tac module. my truck will not keep running.what do you think is wrong.i took the pcm fuse out not knowing what would happen,my check engine light came on and across the dash it read engine power lowered so i put the fuse back the check engine light went out,but since then my truck will not stay running.

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Posted on Jan 02, 2017

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SOURCE: what does failed tac module.

throttle actuator signal sounds like it is stuck closed or the wire to your throttle body is disconnected loose dirty

Posted on Sep 14, 2010

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SOURCE: ..5.7 engine no start.New PCM,cam sensor

i have a 98 chevy 1500 5.7 motor,fuel pump is good,oil pressure switch is good, relay, security not tripped,still wont start, no fuel pressure

Posted on Dec 23, 2010

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Wiring diagram for code u0107 2004 avalanche

Do you even know what DTC U0107 involves ?
DTC U0107
Lost Communications With Throttle Actuator Control (TAC) Module

The throttle actuator control (TAC) module and the powertrain control module (PCM) communicate via a dedicated serial data circuit. This serial data circuit is separate from any other serial data circuit on the vehicle. Accurate transmitting and receiving of serial data requires not only good circuit integrity, but also adequate system voltage. This diagnostic test monitors the accuracy of the serial data transmitted between the TAC module and the PCM. If the PCM detects a loss of data or invalid data, this DTC sets.

Diagnostic Aids
Important: Reprogramming the PCM may cause a communication error between the PCM and the TAC. If the PCM detects a communication error, DTC U0107 sets. Clear any DTCs from the memory that may have been set by Reprogramming.
• DTC U0107 sets if the battery voltage is low. If the customer's concern is slow cranking or no crank because battery voltage is low, ignore DTC U0107. Clear any DTCs from memory that may have set from the low battery voltage condition.
• DTC U0107 sets when there is a short to B+ on the TAC module ground circuit. Inspect the fuses for the circuits that are in the TAC module harness--i.e. cruise, brake. An inspection of the fuses may lead you to the circuit that is shorted to the TAC module ground circuit.
Replace the TAC module. Refer to Electronic Throttle Actuator Control Module Replacement .
Did you complete the replacement?

Nov 20, 2016 | Cars & Trucks

2 Answers


Usually requires a new throttle actuator which may only be available as part of a throttle body assembly

Aug 27, 2016 | 2004 Isuzu Ascender

1 Answer

My H2 2006 jerks forward sometimes while I'm stopped at a light. My mechanic just had it there and no warning lights are on anywhere. Has anyone had that issue?

Have you had it to the dealer ? May have TSB - technical service bulletin. TSB'S are factory technical information publications on know problems with fixes for dealer technicians . May also have up dated soft ware for your vehicles PCM - powertrain control module that may fix this problem . Could have a problem in the
Throttle Actuator Control (TAC) System - Electronic throttle control .Not all problems set trouble codes . And all car manufacturers have some problems with these systems .
The throttle actuator control (TAC) system delivers improved throttle response and greater reliability and eliminates the need for mechanical cable. The TAC system performs the following functions:
Accelerator pedal position (APP) sensing

Throttle positioning to meet driver and engine demands

Throttle position sensing

Internal diagnostics

Cruise control functions

Manage TAC electrical power consumption

The TAC system components include the following:
The APP sensors

The throttle body assembly

The TAC module

The powertrain control module (PCM)

Jun 10, 2016 | Cars & Trucks

1 Answer

Trouble codes chevy p1518

The first check should be done to the TAC module to make sure that none of the wiring near the Control Module is damaged due to chaffing. If the wiring and module appear to be in tact, the procedure below is recommended to correct the P1518
Customers may have a concern of lack of power and engine light on. DTCs set will almost always contain a P1518 and may contain any of the following (P1516, P2108, P0220, P0120, U0107). An improperly torqued TAC module ground may be at fault. The Ground is listed as G104 on TAC module schematic which is incorrectly labeled on SI document ID 855376. The correct ground is G103. The locator for SI states that G103 is located on the left hand side which is incorrect. However, there have been field reports stating that G104 has also corrected this condition. G104 is a horizontal bolt in the rear of the left head and extremely difficult to reach. G104 should also be tightened at the same time.
There have also been field cases where ground G110 on the outer drivers side frame rail caused a P1518 code and an intermittent connection at splice 102 on the intake.
All published SI diagnostics should be followed in addition to following the recommendation listed.
Tighten ground G103 located behind the right cylinder head (passenger side) just below the head and mounted into the block. The ground uses a 13 mm bolt head mounted vertically to the engine block just above the bell housing.

May 17, 2013 | 2001 Chevrolet Suburban

1 Answer

I have a 2004 chevy trailblazer that gave me code p1518

P1518 CHEVROLET Description The Throttle Actuator Control (TAC) module contains data which is essential for proper TAC operation. The TAC module continuously test the integrity of this data. When the TAC module is unable to write or read data to and from random access memory (RAM), or the TAC module is unable to correctly read data from the flash memory or and internal TAC module processor fault is detected and the Detected Trouble Code (DTC) is set.
Read more:

Jul 23, 2012 | 2004 Chevrolet TrailBlazer

1 Answer

No power at three underhood fuses;sensor,ign. module,injector fuses

See if there is another fuse or relay under drivers side dash.

Dec 31, 2011 | 1999 Pontiac Firebird

1 Answer

2009 Ford Fusion codes 2107,2110 car slows to 30mph and will no longer accelerate

Well, those codes definately are related to why your vehicle will no longer accelerate!

P2107 is "Throttle Actuator Control (TAC) Module Processor"
This code means that the TAC portion of the Powertrain Control Module (PCM) has failed the self-test.

Posiible causes:
> TAC motor circuit harness shorted to ground
> TAC motor circuit harness shorted to voltage
> Damage Electronic Throttle Body (ETB)
> Damaged PCM

P2110 is "Throttle Actuator Control (TAC) Forced Limited RPM"

This code is informational only. It sets in conjunction with other throttle actuator control codes (like P2107 above). It is just letting you know that the PCM is limiting RPM due to a TAC malfunction, (So it doesn't do a "TOYOTA" on you and run away!"

Jul 06, 2011 | Ford Fusion Cars & Trucks

1 Answer

2003 Chevy Tahoe 4X4. Started driving and vehicle would not accelerate above 40 MPH. Attached a computer diagnostic to it and it gave a code of P1518.

Tac(throttle actuator control) module to pcm(powertrain control module) circuit problem.Check wire connection on the electric sensor on gas pedal.Most likely just a bad and or dirty connection.See this often on work trucks.

Feb 15, 2011 | Chevrolet Tahoe Cars & Trucks

1 Answer

Waht ist tha p1516

DTC P1516 - Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance


Circuit Description (click over pic for zoom)
The commanded throttle position, based on accelerator pedal position and possibly other limiting factors, is compared to the Actual throttle position. The 2 values should be within a calibrated range of each other. Both the PCM and the TAC module redundantly monitor the Commanded and Actual throttle position. This DTC sets if the TAC module detects the problem.

Conditions for Setting the DTC
1. DTC P1518 is not set.
2. The ignition switch is in the crank or run position.
3. The ignition voltage is greater than 5.23 volts.
4. Not in battery saver mode.
5. The TAC module detects that the commanded and actual throttle positions are not within a calibrated range of each other or the PCM and the TAC cannot determine throttle position or both TP sensors are invalid.
6. All above conditions met for less than 1 second.

Action Taken When the DTC Sets
1. The PCM will illuminate the Malfunction Indicator Light (MIL) when this diagnostic runs and fails.
2. The Reduced Engine Power message displays on the drivers information center.
3. The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Freeze Frame and/or Failure Records.
4. If no other TAC System DTCs are set, the TAC System will operate in Reduced Engine Power mode. If certain TAC System DTCs are set at the same time, the TAC System either defaults to a more tightly restricted mode of operation if the TAC determines that limited safe operation is possible, or the TAC commands the engine to shut down.

Conditions for Clearing the MIL/DTC
1. The PCM turns the MIL OFF after three consecutive drive trips that the diagnostic runs and does not fail.
2. A last test failed (Current DTC) will clear when the diagnostic runs and does not fail.
3. A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
4. The PCM battery voltage is interrupted.
5. Important
* The clear DTC info function may have to be performed twice in order to clear a Throttle Actuator Control System DTC.
* Clear the MIL/DTC information using a scan tool.

Diagnostic Aids
The following may cause an intermittent:
1. Poor connections. Check for adequate terminal tension. Refer to Troubleshooting Procedures, Checking Terminal Contact (Body and Accessories/Wiring Systems) for proper procedure.
2. Corrosion
3. Mis-routed harness
4. Rubbed through wire insulation
5. Broken wire inside the insulation
6. Inspect the TAC module connectors for signs of water intrusion. When this occurs, multiple DTCs should be set and no circuit or component problems can be located.

1. For an intermittent condition refer to Symptoms .
2. If a repair is completed and the DTC was cleared using a scan tool on the same ignition cycle, the default action will not clear until an ignition cycle has occurred.
3. When the TAC module detects a problem within the TAC System, more than one TAC System related DTC may set. This is due to the many redundant tests run continuously on this system. Locating and repairing one individual problem may correct more than one DTC. Keep this in mind when reviewing captured DTC info.

Test Description
The numbers below refer to the step numbers on the diagnostic table.

5. If the TP Indicated Angle does not follow the movement of the throttle blade, and no TP Sensor DTCs are set, there is a mechanical problem with the throttle shaft or the TP Sensor. Replace the throttle body assembly. Re-install the air inlet duct after you complete the repairs.

21. When a problem is detected within the TAC System, more than one TAC System related DTC may set. This is due to the many redundant tests run continuously on this system. It is possible that locating and repairing one individual problem may correct more than one DTC. Keep this in mind when reviewing captured DTC info.







Hope helps.

Feb 10, 2011 | Chevrolet Malibu Cars & Trucks

1 Answer

Engine codes p1518, p0125, and p0420 for 2001 firebird

P0125 sets when engine coolant temp does not reach temperature for closed loop operation within a set amount of time.
May be a faulty sensor or thermostat.
P0420 Is related to a faulty rear 02sensor.
P1518 PCM & TAC module communication detected missing or invalid serial data.
If TAC related repair has been done, clear DTC & recheck system. It may be necessary to preform clear codes function twice to clear this DTC.
make sure starting system & charging system are functioning properly. Low voltage can cause this DTC to set. This should help. Let me know how its going.

Apr 11, 2010 | 2001 Pontiac Firebird

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