by David Ferguson on Wed Jan 15, 2025 11:09 am
That is the normal behavior I see on my PLM.
C3 means the sensor is heating. After 20-30 seconds this will go off and the current Lambda value will be displayed. If there is no active exhaust, then usually you see "--" indictating normal atmospheric oxygen content. If I blow on the sensor, or put in a propane torch flame, it will drop and indicate the Lambda value based on the oxygen content.
Do you have the PLM manual?
Appendix B in the PLM manual says this about the warmup codes:
Warm-up Codes
C-6 Sensor Protection Shutdown. The C-6 state is entered when the PLM
can not pump enough current into the pump cell to balance the sense cell.
When C-6 is entered pump current is turned off. The PLM will try to gain control
of the sensor (the C-1 state) every 10 seconds. If it is then unable to regain
control after 2 seconds then it will re-enter the C-6 state.
C-5 User Stop. The sensor has been turned off via a digital input
C-4 No Heater detected. This will occur if the sensor is disconnected or the
heater is open circuit – ie: the sensor is damaged. Heater circuit should be
approx 3ohms at room temp
C-3 Warm Up. The PLM is heating the sensor prior to normal operation and
waiting for sensor to warm up.
C-2 Control Initialization. Waiting to start pump current
C-1 Checking Operation. Waiting to get control of sensor cell voltage.
In normal operation the PLM will display C-3, C-2, C-1 then start reading lambda
values. The C-4 and C-6 error states will occur if a problem is detected.
If your display is physically upside down, I suspect someone has opened that up and reassembled it upside down. I would probably send it to your MoTeC dealer to have it assembled correctly and tested for functionality.
David Ferguson
Veracity Racing Data