GHP Error Message "Invalid Pump"

This error message "Invalid Pump" means that the autopilot is getting an invalid result when it's trying to read the pump_ID voltage from the encoder. This message could mean one of the following:

• The encoder is not connected

• The encoder has a bad connection

• The encoder is missing the pump_ID resistor

• The encoder has the pump_ID populated with the wrong value

• The analog to digital circuit in the ECU for reading the resistor is bad

To troubleshoot this issue, the connection between the ECU and the pump's encoder needs to be checked. To check this:

1. Power on the autopilot

2. Disconnect the Encoder's cable from the ECU

3. Using a multimeter, check pins 2 and 7 for resistance (ohms) on the Encoder's connector

Here is a diagram showing which pins are 2 and 7.

Here are the correct level of resistance that should be read by the multimeter:

If the resistance is off from what is listed above, the pump will need to be replaced. If the resistance appears to be correct, the ECU will need to be repaired.