U4 voltage at there pins

[cyrilou60230]

hi

what is U4 voltage pins , please ?
especially for pin 5 and 7 ?

regards
cyril

[SymTech Laboratories]

hi

what is U4 voltage pins , please ?
especially for pin 5 and 7 ?

regards
cyril

Pins 5 and 7 switch between 0V and 12V. You should only measure 12V when there's an injection pulse, or if the processor is removed, when pins 2 and 4 are pulled low.

[cyrilou60230]

so i have a problem

with processor unplug and jimstim :
U5 pin 2 = 5v , pin 4 = 5v , pin 5 = 0v and pin 7 = 0v

[SymTech Laboratories]

so i have a problem

with processor unplug and jimstim :
U5 pin 2 = 5v , pin 4 = 5v , pin 5 = 0v and pin 7 = 0v

Do you mean U4? If so, that's all correct. Pins 2 and 4 are pulled high (5V) by two pull-up resistors. If you ground them, you should see U4's outputs, pins 5 and 7, go to 12V.

[cyrilou60230]

ok

so i check voltage grounded pin 2 and 4 and 12v et pin 5 and 7 ok with CPU unplug

so with CPU , the CPU ground pin 2 and 4 or not ?

[SymTech Laboratories]

ok

so i check voltage grounded pin 2 and 4 and 12v et pin 5 and 7 ok with CPU unplug

so with CPU , the CPU ground pin 2 and 4 or not ?

The CPU grounds the pins during fuel injection events. If you looked at the signal with an oscilloscope you would see a square wave, not a flat 0V or 5V DC signal.

[cyrilou60230]

ok

thanks to support me


so we can say U4 is ok ?

U4 is for injector 's bank but injectors pulse are link with rpm varation , i'm right or not ?

so U4 and U3 ( hall coils ) work together , no ?

because at U3 with cpu i have only 5 v at pin 5 and nothing change moving rpm
i have no light at my MS : no D14 + D15 + D16 and no light at my stim ( FP + FIDLE + INJ1 + INJ2 )

i have communication with the MS and CLT + MAT + TPS + O2 + MAP ( stay at 150kpa ) work well


i put the pin 5 of U3 to ground like for U4 and i see rpm + pulse with on my computer and D15 + D16 light

what do you think of it ?


regards
cyril

[SymTech Laboratories]

ok

thanks to support me


so we can say U4 is ok ?

U4 is for injector 's bank but injectors pulse are link with rpm varation , i'm right or not ?

so U4 and U3 ( hall coils ) work together , no ?

because at U3 with cpu i have only 5 v at pin 5 and nothing change moving rpm
i have no light at my MS : no D14 + D15 + D16 and no light at my stim ( FP + FIDLE + INJ1 + INJ2 )

i have communication with the MS and CLT + MAT + TPS + O2 + MAP ( stay at 150kpa ) work well


i put the pin 5 of U3 to ground like for U4 and i see rpm + pulse with on my computer and D15 + D16 light

what do you think of it ?


regards
cyril

Your description of the problem isn't very clear, but it sounds like the ECU isn't getting a proper signal from the crankshaft sensor. Either you have an incorrect setting, the Hall/opto circuit isn't configured correctly, or both.

[cyrilou60230]

i test the light of my like jimstim website
all is ok , all blink for FP , INJ1 , INJ2 , FIDLE , IAC1 , IAC2 with led test
stim rpm work with the test at IAC2 led for primarytach like jimstim website

so jimstim is ok and send all signal

so my MS have a problem
and if with no rpm there is no pulse width so with no rpm no injector opening . it sound good or not ?
so maybe like you say the MS don't have rpm signal

my question is how work rpm signal in MS and what could i control !

cyril