P1512
DTC P1512 Main Throttle Idle Actuator Malfunction (Mechanical Failure)Wiring Diagram:
Circuit Description
The aim of the MTIA (Main Throttle Idle Actuator) is to control the idle speed with the throttle body itself. The throttle is motorized for low opening angle (0 °, 18 °). The characteristics of the air flow are not the same for low and high opening angles. As a matter of fact, the gradient of the mass air flow function of TPS is lower for small angles that permits to be more precise during the idle speed control. Out of idle speed the throttle is actuated mechanically by a classical accelcable.
The DC-motor commands the actuator for idle
Conditions for Setting the DTC
- The engine is running.
- The MTIA set point is between 0.5 ° and 21 °.
- The reference range of MTIA higher than 45% of less than -42% at least 10 seconds.
- Mechanical problems exists.
- problem of accel cable hose
- problem inside MTIA: seizing by friction, snooted, fouling.
Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will illuminate.
- The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.
Conditions for Clearing the MIL/DTC
- The MIL will turn off at the end of 3 consecutive ignition cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 warm-up cycles without a fault.
- DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
An Intermittent problem may be caused by a poor connection, rubbed through wire insulation, or wire that is broken inside the insulation.
Any circuitry, that is suspected as causing the complaint, should be thoroughly checked for the following conditions.
- Backed-out terminals
- Improper mating
- Broken locks
- Improperly formed
- Damaged terminals
- Poor terminal to wire connection
- Physical damage to the wiring harness
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DTC P1512 - Main Throttle Idle Actuator Malfunction (Mechanical Failure)