Subpage of MembersPage/SFiftyBthirtyTwoVanos
BMW S50B32 Vanos subsystem
4 * PFETs (each pair controlled by logically neighbor p259 outputs) are used to drive (switch the +12V high side of) VANOS solenoids
- sectrig (eg 6+1 extra pulse exhaust-cam) => 2 PFETs (controlled via p259/2,3 = pin22,21) wired to exhaust solenoids
- third trigger (evenly-spaced 6 pulse intake-cam) => 2 PFETs (controlled via p259/4,5 = pin67,72 ) wired to intake
- so the "exhaust target" table is actually for the "intake", keep that in mind !
wires for Advance / retard solenoids
With EC36 install, one just connects the output A (advance) and output B (retard) as suggested by [VT help], swapping wires if necessary
- however, with a mot88 frontplate, and factory harness, swapping the (p259 controlled PFET related) outputs / wires is inconvenient, and should NOT be necessary.
[Pieter from DP-engineering] professional installer and reseller kindly reported he diagnosed he swapped physically and acquired perfect VANOS target-follow behavior
- GenBoard/UnderDevelopment/FirmwareChanges with 1.2.40 2018-02-06 fw when inverting the vanos outputs, it will result in swapped advance/retard, like:
- p259/3-2 instead of 2-3
- p259/5-4 instead of 4-5.
If uncertain, we will review any vemslog focusing on Vanos cam behavior. (let us know how it was wired, especially if EC36 install ).
Important:
inverting output (eg. with fw that really inverts, eg. fw different than 1.2.40 2018-02-06) is not the same for dual VANOS as swapping the advance and retard solenoid wires.
- Similar if way off-target, but different behavior near-target. (it "somewhat seemsto work", but not good target-campos-follow)
- During mot88 install/tune if you diagnose cam retard / advance, please
- With any EC36/EC18 ECU always connect the right advance/retard (swapping physically if needed)
- especially with p259/.. controlled NFET (not S50B32 but some other BMW or non-BMW head) invert really needed (to be clear: do not use the 2018-02-06 1.2.40 fw),
To get perfect VANOS result, we recommend to do what is really needed, not the other action:
- swap (EC36 wires or in config with fw 1.2.40 2018-02-06 for mot88 S50B32 only)
- or invert (only with p259 controlled NFETS, not for S50B32)
- how to know ? unlike S50B32 where VANOS is controlled by PFETs; NFET means that the solenoid gets constant +12V, and GND is switched by the driver.
- If "low current" output selected in VT: then "p259/.." controlled
Links:
- Most of the MembersPage/BMW S50B32 are with standard VEMS ECU with econoseal (NOT mot88 frontplate)
- MembersPage/RijaRobinson/SFiftyBthirtyTwoVanos also EC36 install