Does ECU compensate for headlights on S4 ?
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Does ECU compensate for headlights on S4 ?
Hi all:
One quick question ....
On S4, does the ECU compensate when turning the headlights on at idle ??
Does it increase duty cycle of BAC ??
or does it do nothing and assume the engine can handle the increased EMF (electromag force) from the alt ??
Thanks for reading,
hugues -
One quick question ....
On S4, does the ECU compensate when turning the headlights on at idle ??
Does it increase duty cycle of BAC ??
or does it do nothing and assume the engine can handle the increased EMF (electromag force) from the alt ??
Thanks for reading,
hugues -
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Thanks for reply.
Do you know how the ECU sense the added load ?
On S5, there is a load module within ECU that has a pin input from headlight switch, but not on S4.
So, on S4, does ECU look at rpm drop (not consistent with current throttle plate position via TPS reading)
or does it look at something else like voltage drop ?
hugues -
Do you know how the ECU sense the added load ?
On S5, there is a load module within ECU that has a pin input from headlight switch, but not on S4.
So, on S4, does ECU look at rpm drop (not consistent with current throttle plate position via TPS reading)
or does it look at something else like voltage drop ?
hugues -
#5
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No, it's not as sophisticated as you think.  There is not battery voltage compensation.  The BAC valve pulsewidth is set, and it is not variable.  Load it taken by a combination of RPM and pressure inputs - yes, NA still has a "pressure sensor".
-Ted
-Ted
#6
Rotary Freak
The ecu only senses load from items that it has a wire running to.
Power Steering, A/C, headlights and brakes would be good to add a tap into the A/C load or PS load wire to compensate though!
Power Steering, A/C, headlights and brakes would be good to add a tap into the A/C load or PS load wire to compensate though!
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HUGUES: You might be interested in the last response I made to this thread: https://www.rx7club.com/forum/showth...5&pagenumber=2
The turning on of the headlights does indeed have an influence on the operation of the BAC.
Unfortunatly your problem really seems to lie elsewhere. Think ECU.
The turning on of the headlights does indeed have an influence on the operation of the BAC.
Unfortunatly your problem really seems to lie elsewhere. Think ECU.
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