P1124 - FAULT CODE - OBD2

P1124 INFINITI, NISSAN - THROTTLE CONTROL MOTOR RELAY CIRCUIT SHORT

The throttle control motor power supply is provided to the ECM (Engine Control Module) by a throttle control motor relay, which is energized and de-energized as commanded by the ECM. When the ignition switch is placed in the on position, the Engine Control Module sends an ignition signal to the relay and along with this, a battery voltage is given to the ECM. Once the ignition switch turns off the relay is commanded to turn off accordingly and no battery voltage is sent.

When the throttle control motor relay circuit exhibits erratic operation, a series of fault codes will be set. In the case of the P1124 OBDII code, it is a manufacturer-specific code, and for Nissan and Infiniti it means that the circuit is shorted.

• Check Engine lamp comes on.

The reasons why the P1124 OBD2 diagnostic code is set are:

• The throttle control motor relay circuit may have wiring damage.
• An electrical connection of the relay circuit may be poor.
• The throttle control motor relay may be faulty.

The steps to correct the DTC P1124 OBDII code are as follows:

• Start the diagnosis by consulting the Technical Service Bulletins. These contain useful information provided by the manufacturer.
• Perform a scan of the vehicle in order to check if there are other stored trouble codes. If so, repair the codes in the order shown.
• Check the engine relay circuitry that controls the throttle for damage to the wires or connectors. If any of these have defects caused by wear, corrosion, or burns, repairs or replacements should be made.
• Check the continuity of the circuit and the proper resistance of the circuit. The values you obtain should be compared with those indicated in the service manual and if you find values out of range, make the necessary repairs.
• If after inspecting the electrical connections and circuit voltages you find no deficiencies, this indicates that the relay is damaged, replace it.