elrojo27

iTrader: (2)

well i changed out the throttle body and it is still doing this. i read my owners manual and it states that REDUCED ENGINE POWER happenes when the engine is overheating...now i have both fans running and took out the t-stat and the gauges read nothing high than 190. I replaced the coolant and it is still doing this. could it be the throttle control module?? or wiring prob??? would i need to replace the whole harness?

elrojo27

iTrader: (2)

the code it sometimes give is "Loss communication with Throttle Aculator Control"

dc_justin

iTrader: (13)

Throttle control actuator (TAC) is located on the drivers side firewall. Check all connections there for a loose wire, corrosion or dirt/water.

elrojo27

iTrader: (2)

is it the black box right on the engine side firewall?? has two connections under it.

dc_justin

iTrader: (13)

That's the one. Disconnect those things, clean them all out and re-attach.

Justin

1SlowHoe

iTrader: (28)

That DC_Justin guy knows what he's talking about.
I'd maybe clean the MAF as well.

DrX

iTrader: (7)

Does this DTC set alone or in conjunction with other DTCs?

Here's some information related to DTC U0107:
"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.
• DTC U0107 sets if the TAC module ignition feed circuit is shorted to a B+ supply circuit. The TAC module stays powered-up when the ignition switch is turned OFF. When the ignition switch is turned ON, the TAC module is powered-up before the PCM. DTC U0107 sets because no communication is detected by the TAC module from the PCM. Inspect related circuits for being shorted to a B+ supply circuit.
• Inspect the TAC module power and ground circuits and the TAC module/PCM serial data circuits for intermittent connections.
• Inspect the TAC module connectors for signs of water intrusion. If water intrusion occurs, multiple DTCs may set without any circuit or component conditions found during diagnostic testing.
• 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 an individual condition may correct more than one DTC. Remember this if you review the stored information in Capture Info.
• For an intermittent condition, refer to Intermittent Conditions . "

DrX

iTrader: (7)

Here is the diagnostic chart from the service manual for this DTC:


"Test Description

The numbers below refer to the step numbers on the following diagnostic table.

1. This step determines if the ignition relay is supplying a voltage to the ETC fuse.
   
   Increasing the engine speed to 3,000 RPM aids in locating a shorted throttle actuator motor control circuit. Depending on the polarity of the throttle actuator motor transistors, this DTC may not set with a fault in the control circuits. The throttle actuator motor is a bi-directional DC motor. Raising the engine speed changes the polarity of the transistors in the throttle actuator motor. This occurs because one set of the transistors is low, 0 volts, and the other set is high, B+. Therefore, if one set of transistors is at a low voltage and the corresponding circuit is shorted low, DTC P1518 will not set. When the polarity of the transistors change, this DTC sets. If this DTC does not fail this ignition, continue to monitor this DTC status while moving related harnesses and connectors.
   
   Locating and repairing an individual condition may correct more than one DTC.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views


1 Did you perform the Diagnostic System Check - Engine Controls?


Yes-Go to Step 2

No-Go to Diagnostic System Check - Engine Controls

2 Turn ON the ignition, with the engine OFF. Remove the cover from the underhood electrical center.

1. Test both sides of the ETC fuse with a test lamp connected to ground. Does the test lamp illuminate on at least one side of the fuse?

Y-Go to Step 3

N-Go to Ignition Relay Diagnosis

3 Turn OFF the ignition

1. Test for voltage at the ETC fuse with a test lamp connected to ground. Does the test lamp illuminate?

Y-Go to Step 22

N-Go to Step 4

4 Connect a scan tool. Is DTC P0604 also set?

Y-Go to DTC P0601-P0607, P1600, P1621, P1627, P1680, P1681, P1683, or P2610

N-Go to Step 5

5 Important

If the Driver Information Center is displaying Reduced Engine Power, go to Step 6.

1. Start the engine. Increase the engine speed to 3,000 RPM, if possible.
2. Monitor the DTC Info option using the scan tool.

Does the scan tool indicate this DTC failed this ignition?

Y-Go to Step 6

N-Go to Diagnostic Aids

6 Turn OFF the ignition. Disconnect the throttle actuator motor harness connector. Turn ON the ignition, with the engine OFF.

1. Test for voltage at both throttle actuator motor control circuits with a DMM. Does the DMM indicate voltage on both circuits above the specified value? (1 V)

Y-Go to Step 12

N-Go to Step 7

7 Turn OFF the ignition. Disconnect the throttle actuator control (TAC) module connectors.

1. Test both throttle actuator motor control circuits for continuity to ground with a DMM. Does the DMM indicate continuity to ground?

Y-Go to Step 10

N-Go to Step 8

8 Turn OFF the ignition. Remove the ETC fuse.

1. Test the TAC side of the fuse terminal for continuity to ground with a DMM. Refer to Diagnostic Aids for terminal identification table.

Does the DMM indicate continuity to ground?

Y-Go to Step 9

N-Go to Step 11

9.

1. Disconnect the TAC module 16-way harness connector.
2. Test the TAC side of the fuse terminal for a short to ground with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 24

10

1. Disconnect the TAC module 16-way harness connector.
2. Test the throttle actuator motor control circuits for a short to ground at the TAC module 16-way harness connector with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 24

11

1. Turn OFF the ignition. Disconnect the TAC module 16-way harness connector.
2. Test the TAC module ignition feed circuit for an open or high resistance with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 24

12

1. Turn OFF the ignition. Disconnect the TAC module 16-way connector. Turn ON the ignition, with the engine OFF.
2. Test for a short to voltage at both throttle actuator motor control circuits with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 13

DrX

iTrader: (7)

More:




13

1. Turn OFF the ignition. Disconnect the TAC module 10-way harness connector.
2. Test for a short between each throttle actuator motor control circuit and all other TAC module circuits with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 14

14 Test for an open or high resistance in the TAC module ground circuit with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 15

15 Test for voltage on the serial data circuits at the TAC module 16-way harness connector with a DMM. Does the DMM indicate voltage within the specified values for both circuits? (0-4.5 V)

Y-Go to Step 16

N-Go to Step 18

16 Turn OFF the ignition.

1. Test both serial data circuits at the TAC module 16-way harness connector for continuity to ground with a DMM.

Does the DMM indicate OL for both circuits?

Y-Go to Step 20

N-Go to Step 17

17

1. Disconnect the powertrain control module (PCM) connector containing the TAC module serial data circuits.
2. Test both serial data circuits at the TAC module 16-way connector for a short to ground with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 18

18 Test for a short between both serial data circuits and all other circuits at the PCM and TAC module harness connectors with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 19

19. Test for a short to voltage on both serial data circuits at the TAC module 16-way connector with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 25

20

1. Disconnect the PCM connector that contains the TAC module serial data circuits.
2. Test each serial data circuit between the TAC module 16-way harness connector and the PCM harness connector for an open or high resistance with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 21

21

1. Connect the PCM. Turn ON the ignition.
2. Test for voltage on the serial data circuit at the TAC module 16-way harness connector with a DMM.

Does the DMM indicate voltage at the specified value? (0 V)

Y-Go to Step 25

N-Go to Step 24

22

1. Turn OFF the ignition. Disconnect the 16-way TAC module harness connector.
2. Test the TAC module ignition feed circuit for a short to battery voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 23

23

1. Turn ON the ignition.
2. Test both TAC motor circuits for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 24

24

Test for poor connections at the TAC module harness connector. Refer to Testing for Intermittent and Poor Connections and Repairing Connector Terminals in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 26

DrX

iTrader: (7)

The rest:

25 Test for poor connections at the PCM harness connector. Refer to Testing for Intermittent and Poor Connections and Repairing Connector Terminals in Wiring Systems.

Did you find and correct the condition?

Y-Go to Step 28

N-Go to Step 27

26 Replace the TAC module. Refer to Throttle Actuator Control (TAC) Module Replacement .

Did you complete the replacement?

Y-Go to Step 28


27 Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement .

Did you complete the replacement?

Y-Go to Step 28

--

28

1. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine.
2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

Y-Go to Step 2

N-Go to Step 29

29

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?


Y-Go to Diagnostic Trouble Code (DTC) List

N-System OK "