2i not giving out 5 Volts
05-13-10, 08:49 PM
#2
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Key ON?
1A and 1B have power????
The 3A, 3B, 3C and 3D all going to gnd with less than .2ohms on them?
What are you getting on 2I??????
Do you have batt pwr on all four fuel injector wires at the ECU plug?
IF you have pwr on the 1 and 1B, then I"d pull all the engine sensors off their components and check 2I once more.
Dead ECU could be the problem. No ref voltage............not start no run ever.
1A and 1B have power????
The 3A, 3B, 3C and 3D all going to gnd with less than .2ohms on them?
What are you getting on 2I??????
Do you have batt pwr on all four fuel injector wires at the ECU plug?
IF you have pwr on the 1 and 1B, then I"d pull all the engine sensors off their components and check 2I once more.
Dead ECU could be the problem. No ref voltage............not start no run ever.
05-14-10, 08:16 AM
#3
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Thread Starter
Yeah key on 
1a+b have power
Injectors hvae power
So does coils, pump and CEL connector, but no codes are thrown obviously because of lack of power to the sensors.
Honestly I havent checked the grounds.
What I do have is, 186 Ohms between 2i and ground.
Will check the printboard for burnt components monday.
1a+b have power
Injectors hvae power
So does coils, pump and CEL connector, but no codes are thrown obviously because of lack of power to the sensors.
Honestly I havent checked the grounds.
What I do have is, 186 Ohms between 2i and ground.
Will check the printboard for burnt components monday.
05-14-10, 08:38 AM
#4
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Again, with all ECU plugs connected up, what is your reading on 2I????
2I is an OUTPUT from the ECU.
IF the plug is off and you OHM out 2I (the wire in the harness plug), your ohming thru several sensors (TPS, boost, etc) to ground. This reading has no validity.
With all ECU plugs connected up and key ON, the 2I ouputs what they call ref voltage to the sensors. Approx 5vdc.
If you are reading 2I with meter on volts dc and all connectors connected up, and you read a smallish figure like 2-3vdc, then pull all the elec plugs off the related sensors and see what/if that voltage is now in the 5vdc range.
IF this car presently starts and idles/runs/drives...............ain't nothing wrong with 2I and it does probably read close to 5vdc with key ON and all ECU connectors connected.
2I is an OUTPUT from the ECU.
IF the plug is off and you OHM out 2I (the wire in the harness plug), your ohming thru several sensors (TPS, boost, etc) to ground. This reading has no validity.
With all ECU plugs connected up and key ON, the 2I ouputs what they call ref voltage to the sensors. Approx 5vdc.
If you are reading 2I with meter on volts dc and all connectors connected up, and you read a smallish figure like 2-3vdc, then pull all the elec plugs off the related sensors and see what/if that voltage is now in the 5vdc range.
IF this car presently starts and idles/runs/drives...............ain't nothing wrong with 2I and it does probably read close to 5vdc with key ON and all ECU connectors connected.
05-14-10, 04:56 PM
#5
OBEY YOUR MAZDA
Thread Starter
Hehe sorry 
2i shows 0 --> 0,2Volts
I'm starting to think it might be the ecu itself, owner did have trouble starting it last summer(flood)
Could be current-spikes from boosterpacks or dino-chargers fried a pcb track
2i shows 0 --> 0,2Volts
I'm starting to think it might be the ecu itself, owner did have trouble starting it last summer(flood)
Could be current-spikes from boosterpacks or dino-chargers fried a pcb track
05-14-10, 09:05 PM
#6
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2I should be a brown/white wire and if it's plug is connected to the ECU and key ON, then it should show approx 5vdc. Like I say, disconnect the plugs from the afm, tps, omp, boost sensor, and see if the 5vdc suddenly appears. If not.........bad ECU in my opinion.
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