DTC 15 (4) Throttle Motor Circuit Malfunction
DESCRIPTION
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The fully open position of the throttle valve is detected by the throttle open switch mounted on the venturi.
If this DTC is stored, the ECM shuts down the power for the throttle control motor.
| DTC No. | DTC Detection Condition | Trouble Area |
| 15 (4) |
Open or short in the throttle control motor circuit. | Open or short in throttle control motor circuit
Throttle control motor
Throttle valve
Open or short in throttle open switch circuit
Throttle open switch
ECM
|
| Open or short in the throttle open switch circuit. |
WIRING DIAGRAM
INSPECTION PROCEDURE
- Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.
| 1.INSPECT DIESEL THROTTLE BODY (THROTTLE OPEN SWITCH) |
Inspect the throttle open switch (See page ).
| | REPLACE DIESEL THROTTLE BODY
|
|
|
| 2.CHECK HARNESS AND CONNECTOR (THROTTLE OPEN SWITCH - ECM AND BODY GROUND) |
Disconnect the throttle open switch connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance (Check for Open):
| Tester Connection | Condition | Specified Condition |
| C110-1 - Body ground | Always | Below 1 Ω |
| C102-15 (THOP) - C110-2 | Always | Below 1 Ω |
- Standard Resistance (Check for Short):
| Tester Connection | Condition | Specified Condition |
| C102-15 (THOP) or C110-2 - Body ground | Always | 10 kΩ or higher |
Reconnect the throttle open switch connector.
Reconnect the ECM connector.
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 3.CHECK ECM (THROTTLE CONTROL MOTOR CIRCUIT) |
During engine racing, check the waveforms according to the value(s) in the table below.
- OK:
| Tester Connection | Condition | Specified Condition |
| C101-10 (LU+A) - C101-13 (E01) | Engine racing | Correct waveform is as shown |
| C101-9 (LU-A) - C101-13 (E01) | Engine racing | Correct waveform is as shown |
| C101-8 (LU+B) - C101-13 (E01) | Engine racing | Correct waveform is as shown |
| C101-7 (LU-B) - C101-13 (E01) | Engine racing | Correct waveform is as shown |
Text in Illustration| *a | Component with harness connected
(ECM) |
| *b | Signal waveforms |
| 4.INSPECT DIESEL THROTTLE BODY (THROTTLE CONTROL MOTOR) |
Inspect the throttle control motor (See page ).
| | REPLACE DIESEL THROTTLE BODY
|
|
|
| 5.CHECK HARNESS AND CONNECTOR (THROTTLE CONTROL MOTOR - ECM) |
Disconnect the throttle control motor connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance (Check for Open):
| Tester Connection | Condition | Specified Condition |
| C105-6 - C101-10 (LU+A) | Always | Below 1 Ω |
| C105-4 - C101-9 (LU-A) | Always | Below 1 Ω |
| C105-3 - C101-8 (LU+B) | Always | Below 1 Ω |
| C105-1 - C101-7 (LU-B) | Always | Below 1 Ω |
- Standard Resistance (Check for Short):
| Tester Connection | Condition | Specified Condition |
| C105-6 or C101-10 (LU+A) - Body ground | Always | 10 kΩ or higher |
| C105-4 or C101-9 (LU-A) - Body ground | Always | 10 kΩ or higher |
| C105-3 or C101-8 (LU+B) - Body ground | Always | 10 kΩ or higher |
| C105-1 or C101-7 (LU-B) - Body ground | Always | 10 kΩ or higher |
Reconnect the throttle control motor connector.
Reconnect the ECM connector.
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| OK | |
| |
| CHECK ECM POWER SOURCE CIRCUIT
|
|
