If the "earth" through the ECU isn't working it suggests that something is amiss with the ECU.Found time to check Lambda heater and found it was not working. No voltage on loom plug to sensor.
Checked cable through loom from heater relay earth to ECU pin 36, all good. Checked cable from relay output to Lambda plug, all good. ECU plug pin 28 checked to body earth, all good.
Also checked both 12 volt inputs to the relay, again all good.
Earthed heater relay coil by connecting a separate cable to the body and relay operated. With this connected i had the supply to the Lambda heater. It would appear that the relay is not getting the earth path through the ecu
I also checked the PTC relay earth to the ecu pin 6 and found 12 volt on that cable. Again if this relay was getting earthed through the ecu the heater would work.
Is there any way i can check the earth path through the ECU or does it need to be sent away to a specialist company?
What model is it to see if we can find a spare in Scottishmini
FS