Throttle Valve Potentiometer
| Measurement: | Plot of voltage at the signal output of the potentiometer. |
|---|---|
| Check Objective: | Checking the electrical and mechanical functions. |
Preparation
Switch off the engine and ignition.
Connections
| INPUT A | COM/TRIGGER |
|---|---|
| Connect the red measurement lead to pin 3 (C) of the connection plug on the throttle valve potentiometer. Connect the ground lead to pin 2 (B). |
Procedure
Switch on ignition.
Depress the accelerator pedal quickly down to the limit stop and then release it again.
Reference Curve
Fault Scheme 1
Symptoms:
Plot of signal is overlaid with interference spikes or has downward pointing disruption.
| Possible Causes | Countermeasures |
|---|---|
| Faulty throttle valve potentiometer. | Replace throttle valve potentiometer. |
Fault Scheme 2
Symptoms:
Signal plot has stepped plot.
| Possible Causes | Countermeasures |
|---|---|
| Faulty throttle valve potentiometer. | Replace throttle valve potentiometer. |
Fault Scheme 3
Symptoms:
Signal plot is overlaid with considerable noise.
| Possible Causes | Countermeasures |
|---|---|
| Ground lead connected to the engine ground. | Connect the ground lead to pin 1 (B) of the connection plug. |