I have noticed that V3.8 have some differences when adding third trigger.
- maybe you want to detail what you noticed
- Effectively same usage as v3.7:
- find SDA pin (throughole pad of small 2 pin header, see below)
- with the cam-HALL sensor: pull "SDA pin" to GND, or apply 0/5V signal
- enable 3rd trigger in config
I have made the same circuit i used on ma 3.7 board but on the 3.8 board it does not seem to work?
- the components for third trig protection (diode, and capacitor) are onboard for v3.8 (but adding another set would not cause any noticable effect).
- if you really made same circuit, it should work
- maybe you can detail the exact circuit (component by component, see the snippets from VT help below as a guide), so there is at least some chance someone can help
[VT Help] says "Use Pull-up resistor, a 10k protection resistor, and protection Diode, and a 22nF capacitor (min 10nF) between processor pin and GND."
- This is exactly what i did, I had this on a 3.7 unit, and a moved it all over to this unit. Does not work. Thanks for the guide, will measure everything, might have made a mistake somewhere - ENGDAHL
Only essential components: "Pull-up resistor, a 10k protection resistor"
- (v3.8 has protection diode and capacitor anyway)
With that in mind, the minimum info in a request would be :
Third trigger input
- Your pullup resistor value ? (typ 2k7)
- voltage measured on (HALL type) third trigger input ? (input open and shorted to GND).
- your series resistor value ? (typ 10k)
- voltage measured at processor SDA pin ? (should be >4V with input open and <0.8V with input shorted to GND)
- diode towards +5V present or not ?
- diode towards GND present or not ?
- BAV99 combines both these diodes in a sot23 package
I read somewhere about some capacitor need changing?
- where do you read ?
- Maybe you read that "max 1nF" for Nissan sectrig ?
- that is not relevant for third trig, (or non-Nissan), and even for Nissan sectrig, although a checklist item, should be good by default since 2011
Please write a complete guide of what needs to be done for third hall trigger on 3.8 board.
- See [VT Help] about third trigger (camshaft angle control).
- shape signal so that it's a logic signal, and connect it to the processor input (really-really simple, just a series resistor for HALL type ; or a separate circuit with VR=>HALL adapter for VR)
- see GenBoard/VerThree/Schematic
- detail what you have found and changed, and measured
- otherwise just order [ECU] with third trigger
- normally thirdtrig is same type as secondary trigger (typically HALL, rarely VR)
I'm trying to change this v3 s/n 9422 from VR/VR (well: it is VR/HALL in the first place) to HALL/HALL/HALL
Atleast I think it was VR/VR because is has the second LM chip.
Whats strange though is that the blob under the FETS was open
- blob under the FETs open => So sectrig is HALL (even if it has secondary LM1815)
- so everything suggests secondary_trigger: HALL
But when I try to ground the signal on Pin 13 It looks like VR interference, not clean signal.
- I don't understand the "looks like VR interference" part. Can you scope it ?
- With HALL, a DVM can be used, fill in same measurements as for third trig (see above).
- First do NOT ground, just measure voltage on input with nothing connected.
And no signal on third what so ever. Have I just forgotten some settings in VEMStune maybe?
- enable third trigger => the chosen edge transitions should show up in triggerlog
- Can you confirm that (measured on SDA pin), voltage changes between say 0.1V and 4.2V ?
'''v3/9422 orig specs (might have been changed since than)
ECU VEMS V3
- - primary_trigger: EC36/27 VR
- - secondary_trigger: HALL
- - EGT input: 1
- - Flyback: LowZ active flyback 8ch
- - ignition driver: 8
- - Knock input channels: 0
- - LCD connection: no
- - MAP connection: 400kPa (6/4mm pneumatic)
- - mounting-style: no-screws
- - 1-wire interface: no
Does it match ?
- SDA pin is 3rd trigger input (pull to GND, or apply 0/5V signal: effectively same usage as v3.7, just less likely to damage something because of added protection)
- R116 2k7 Pull-up resistor
- R114 10k protection resistor
- D55 BAV99 protection didode
- C105 1nF filter capacitor