The DTC U0107 Lost Communication With the Throttle Actuator Control (TAC) Module diagnostic monitors the communication between the TAC module and the powertrain control module (PCM). The TAC module and the PCM communicate on a serial data line. If the PCM can not communicate with the TAC module, DTC U0107 sets.
This diagnostic procedure supports the following DTC:
DTC U0107 Lost Communication With the Throttle Actuator Control (TAC) Module
• | DTC P0122, P0123, P0222, P0223, P0641, P0651, P2100, P2101, P2108, P2122, P2123, P2127, P2128, P2135, P2138, and P2176 are not set. |
• | The ignition is ON. |
• | Battery voltage is at least 8 volts. |
• | DTC U0107 runs continuously once the above conditions are met. |
Either of the conditions below is present for at least 250 milliseconds:
• | The PCM did not detect any signal on the serial data line. |
• | The serial data signal is unreadable. |
• | The PCM illuminates the malfunction indicator lamp (MIL). |
• | The PCM records the operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame buffer. |
• | The MIL turns OFF after 3 consecutively passing trips without a fault present. |
• | A history DTC clears after 40 consecutive warm-up cycles without a fault. |
• | Perform the scan tool Clear DTC Information function. |
The numbers below refer to the step numbers on the diagnostic table.
The Diagnostic System Check - Vehicle prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool, if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
This step checks for an open in the ignition positive voltage supply to the TAC module.
This step checks for an open in the TAC module electrical grounds. The TAC module can not operate correctly if there are faulty electrical grounds.
After replacing the PCM, a new minimum throttle position and idle speed must also be established.
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views | ||||
Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | ||
2 |
Is a DTC U0107 set? | -- | Go to Step 4 | Go to Step 3 |
3 |
Does the DTC run and pass? | -- | Go to Step 4 | Go to Intermittent Conditions |
4 | Is a DTC P2554 or P2555 also set? | -- | Go to Step 5 | |
5 |
Is the voltage at the specified value? | B+ | Go to Step 6 | Go to Step 10 |
6 | Connect the DMM to the ETC signal circuit and a good ground. Is the voltage at the specified value? | B+ | Go to Step 7 | Go to Step 11 |
Connect the DMM to the ignition positive voltage circuit and ground. Is the voltage at the specified value? | B+ | Go to Step 8 | Go to Step 13 | |
Probe each TAC module ground circuit with a test lamp connected to B+. Did the test lamp illuminate on both ground circuits? | -- | Go to Step 9 | Go to Step 12 | |
9 |
Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 14 |
10 |
Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 16 |
11 |
Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 16 |
12 | Repair the open in the ground circuits of the TAC module. Refer to Wiring Repairs . Did you complete the repair? | -- | Go to Step 18 | -- |
13 |
Did you complete the repair? | -- | Go to Step 18 | -- |
14 |
Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 15 |
15 |
Did you complete the replacement? | -- | Go to Step 18 | -- |
16 |
Did you find and correct the condition? | -- | Go to Step 18 | Go to Step 17 |
Did you complete the replacement? | -- | Go to Step 18 | -- | |
18 |
Does the DTC run and pass? | -- | Go to Step 19 | Go to Step 2 |
19 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK |