If a certain VEMS ECU is ordered with "Dual WBO2 requested" (option, or order comment), this should NOT be needed.
Provided for reference (during some debug/diagnostics, or if converting an old device ordered without Dual WBO2).
2nd WBO2 hardware channel on v3.x. Verification of this doc is in progress, use GenBoard/VerThree/Schematic for now.
Problem: When I bench test/calibrate:
- GOOD: Gnd to pump- is 4V as desired both controller channels
- GOOD: pump- to pump+ is -2mV, as desired both controller channels
- OOPS: pump- to nernst is ~260mV and I can't get the value up near 450mV no matter what I use for wbo2_nernst_dc_target.
I notice the second heater stops heating when the pump- to nernst goes positive (when it normally goes to 450mV).
Thoughts on this? I'm using 2 resistors ( pump- 100 Ohm nernst 100 Ohm pump+), as outlined in the Hardware Test page.
- Should I use the 100 Ohm resistors on both channels at the same time ?
- we definitely test that way. Please try,
- and measure resistor values (just in case), and pump+ voltage also (double of nernts, when measured from pump- as a base)
- although should work to calibrate them individually
Gnd to Pump- 4.00V
Pump- to Pump+
wbo2-1: -0.8mV
wbo2-2: -2.0mV
Pump- to Nernst
wbo2-1: 244mV
wbo2-2: 270mV
- Note, VemsTune "Calibrate first channel" appears to start both channels. "Calibrate second channel" appears to start both channels as well. Latest VemsTune nightly and ini files updated.
I'll document the process similar to GenBoard/Manual/WideBandHardwareTest once I understand what I'm missing with this dual wideband testing.
First we review your actual configuration
- 2nd WBO2 enabled ? most likely, but please check
- Yes
- [dummy config] (outputs disabled), enable 2nd WBO2 manually
- vemscfg and vemslog. http://vems.hu/vemstune/sharingcenter/reports.php?cmd=view&key=TjRWqk It might not be impossible to reporoduce the setup that way. (although something simple HW thing is more likely, like something interfering near EC18 /1 ?)
- Hi, as I understand you are modifying existing vems board, have you guys removed solderblobs for wheelspeed 1 and knock 1, I remember I had some bad experience when was trying to make second wb working, those were the problem. Valdas. And btw, you seem to be missing c26 in your list of modifications.
- Thanks! I'll try that. If C26 is the problem, it's documented wrong because it's stated to be part of the 1st channel components. It's missing on the board, so I'll check to see if it alters behavior. Already took care of the solderblobs for knock/wheelspeed and the one for second wbo2. I need to add that SJ18 (bottom side) to my picture.