- Support required for VEMS Lambda sensor
- After VEMS support had to change ecu board from the #10267 (for the issues descripted below in this page) to the new #15379,
Everything returns fine again for few minutes if you switch off and on the engine.
Is there a way, looking at the logs, to understand what's going wrong in lambda sensor/v3 ecu controller?
I may add that this happens only after VEMS Support changed his ecu board, and never happened in 2500 kms with the old board.
Current fw is 1.2.38.
- Support for ecu serial #10267
- A customer's V3.6 ecu suddendly lost serial number, seems to be in a kind of limp mode (10° and 0.65 lambda at any load/rpm).
- VemsTune is now displaying that Serial is unknown-0.
Granting (by info sent in priv),
Do you have ISP cable (Parport DSUB25 or USB-ISP ?) Will need to follow
http://vems.hu/vt/help/v3/general/bootloader_upgrade.html
If considering bootloader upgrade, (so that internal BOD can be disabled) highly recommended:
PLEASE CHECK THAT v3/10267 has reset chip at the atmega128/pin20 reset, eg
- mcp121 or mcp131 (U26 position)
- or mcp809 or max809 (U10 position)'''
See GenBoard/VerThree/Schematic eg
- Support required for VEMS EGT amplifier
Engine off, ambient sensor temp (~20C)
- Tested Pin7 DVM output (1V/100°C) and getting 0.7 volts
- corresponding to 70C
- not 6 volts, roughly corresponding to Pin6 2.5 volts.
- I'm getting 2.5 volts out of Pin6 (0-5V output, 1V/233.3C)
- Thus getting 580°C instead of 20°C.
Hint: The output is almost certainly connected to an input with pullup (possibly strong pullup).
- Diagnostic: disconnect anything from output, and measure DC voltage with DVM (the DVM has 1 to 10MOhm input impedance).
- Solution: make sure to connect pin6 output to an input without pullup resistor
Sensor connection (seems good):
EGT sensor is K type yellow-red wires:
- yellow = green (plus wire) to board GND
- red = white (minus wire) to the board cathode on corner