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FIXED BAD ECM ,Suzuki experts 2010 Suzuki equator 4.0 a crank no start
OK I got time to do more testing today key on engine off voltage drop 5 v reference circuit
Ckp-cmp bnk1 cmp bank 2 all had (10 v)
Ect- maf (.20 volt)
Weird right!
Now the crankshaft and camshaft position sensors are on the same circuit Diagram shows they are 1st internally grounded by the ECM And then the ecm is grounded through the body which that body ground wire is good
As far as ECT and MAF sensors with no voltage Those sensors are supplied voltage by the ecm
So I obviously have a issue where the ecm is not grounding out my sensor's properly and not supplying my sensor's with power either
As other weird problem I have 7 vollts coming through a engine ground wire that initially grounds the Ignition coils which those also route to the ECM as well via diagram
Guys it looks like I need ecm Badd part is Suzuki went out of business so it's hard to find a Nissan dealership that actually wants to reprogram/re Flash one for me , And then I'm looking for a used one
Are you measuring voltage or measuring voltage drop? You should be measuring voltage at a sensor for 5v ref and go ahead and measure signal and ground there as well (ground lead connected to battery negative positive lead taking measurements, meter set to 20v scale). Slow down on that ecm thing I'm 99% sure you don't need 1.
Reading 7v on a ground wire suggests that circuit is powered up and the ground is bad. It sound alike your saying this is a computer ground side switched circuit in which case the ground that feeds that transistor would need to be tested
Voltage drop measuring grouded on negative of battery , Yellow lead across signal wires and I also tested ground wires on the sensor's The grounds were a little noisy but They were around .030 mv why would you think I don't need ecm
I'm not sure I understand what test you have done were looking for a voltage measurement on the 5v ref circuit. if your measuring voltage drop that would be the difference between battery voltage and what is available on a powered circuit . We're only interested in voltage drop on the ground wires to the ecm. After that were looking for a voltage reading on the 5v ref circuit and a voltage reading on the powers that feeds the the sensor were also looking for voltage on the sensor ground wire if there is no voltage on the ground wire and neatly no voltage on the 5v ref then were looking for a shorted sensor pulling the 5v down if there is high voltage on the 5v and may be accompanied with high voltage on the sensor ground then were looking for a computer ground.
You should be checking the ecm power and ground directly at the ecm going through the diagram 1 by 1 with key on engine off voltage reading on powers and voltage drop on grounds.
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I was checking for voltage on my 5 v reference signal circuit not sure why I said voltage drop my mistake, The readings that I found are listed above crank and cam sensors had 10 V on signal 12v on ignition
Mass airflow and ect Had basically 0.20 V signal 12v ignition
So it’s obvious I have ground issues and power issues
I am also aware of that a sensor can be pulling my voltage down
I also did my voltage drop test on the sensor ground wires and they carry no voltage
My next step is to recheck the grounds directly at the ECM I will put it at a 1v scale to get a closer look at them
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