T8 / P1523 00

Read the instructions below then start the fault diagnostic procedure.

Symptom: Fault indicator lamp (for further information see WIS Fault diagnosis, general) Cruise control not working. Limp home

P1523 00

Fault symptom

Fault indicator lamp (for further information see WIS Fault diagnosis, general)

Cruise control not working.

Limp home

On-board diagnosis

Type of diagnosis:

Continually

Enable criteria:

When the ECM is awake, diagnosis is active (even with the ignition off).

Test 1

•	Engine is not running.

•	Throttle position requested in rest position to conserve current.

Test 2

•	Engine running.

•	Throttle position requested in rest position due to system reaction to another DTC.

Fault criteria:

Test 1

•	The throttle has a > 41% variation from rest position for 0.6 s.

Test 2

•	There is no signal from the throttle position sensors and the air mass flow rate is > 23g/s for 0.15 s.

Each time the voltage across the throttle motor is disengaged, the throttle returns to its starting position.

Dependent:

None

System reaction to a fault:

Test 1

•	Correction of mass air flow/combustion for fuel calculation is blocked.

•	Limited acceleration and idle function.

•	Cruise control blocked.

•	Secondary air injection function is disengaged if the secondary air injection pump is fitted.

Test 2

•	Engine shut off.

OK report:

Approximately 3 to 5 seconds after the ignition is switched off, when the throttle resumes rest position.

Fault handling:

Type III

(See section Fault handling III, "Other emission-related components and functions" for more information.)

Checking the wiring harness

Move the wiring harness at several spots and in several directions to reveal intermittent breaks and short-circuits. Check switches, connectors and crimp connections for oxidation, retracted pins and pin clamping force.

Diagnostic help

Diagnosis regards:

Electrical fault in connecting leads or component.

Mechanically binding/affected throttle.

P1523 is generated if the throttle is moved (e.g. with a screwdriver) when in the rest position, even when the ignition is off.

Functions in the diagnostic tool related to the fault:

Test value:

•	Throttle Position Sensor 1

•	Throttle Position Sensor 2

Activation:

•	Throttle Position Test

(See also description of readings/activations in diagnostic tool)