P1785

DIAGNOSTIC TROUBLE CODE IN THE AF22 SYSTEM P1785
Throttle position information to the AF22 control module faulty.

Diagnostic Procedure.
1. With the ignition switched OFF, connect the BOB to the MOTRONIC control module and its cable.
Start the engine and measure the signal across pins 52 and 14. The signal is a 100 Hz PWM signal and its voltage should be:
- about 1.3 V at idling speed
- about 2.2 V at 2500 rpm
- about 12 V at full throttle

2. If the signal is wrong or absent, check the throttle position sensor.

3. If the throttle position sensor is OK and the signal from pin 52 wrong or absent, continue at "Before Control Module Replacement" for further diagnostic instructions. Before Replacing A Control Module