DE6 - Check Stability of FF Sensor Signal Output Frequency

- Key "OFF".

- Flexible Fuel (FF) sensor connected.

- Breakout box installed, Powertrain Control Module (PCM) connected.

- Connect the Rotunda Megameter 014-00768 or equivalent to the breakout box in the following manner:

- Red lead to test pin 45.

- Black lead to battery negative post.

- Select the frequency mode on the meter.

- Key "ON".

- Observe the frequency display of the meter.

- Does the frequency measurement fluctuate erratically within the 40 to 160 Hz range?

Yes -- Go to DE7. DE7 - Check For Fuel Separation

No -- Go to DE9. DE9 - Perform Fuel Composition Test