Crank Position Sensor problem
#1
On The Tree
Thread Starter
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Hi Guys,
My motor is a Small Block Chev 400, but its running the 0411PCM, 24 tooth reluctor and coil per cylinder ignition, so I guess this is the best place to post it.
Long story short, I am ready to fire up my motor in my '85 TransAM with a modified VX LS1 harness and PCM, but there is no spark and no fuel.
Everything else on the PCM checks out, VATS removed, turn ignition and fuel pump primes, turn the key and the engine cranks, but the PCM isn't receiving the cranking signal.
I did a check and the Crank sensor (Vortec L31 type) is getting 12v and ground, but the signal wire is putting out a constant 1.30v DC regardless of reluctor wheel position, or even when its removed from the hole.
From what I've read online, this sensor should only output wither 5v or 0v is this correct?
Its a brand new sensor from EFIConnection so I wouldn't expect it to be faulty, but its the only explanation I can come up with.
Here's the reluctor wheel alignment, does this look right?
My motor is a Small Block Chev 400, but its running the 0411PCM, 24 tooth reluctor and coil per cylinder ignition, so I guess this is the best place to post it.
Long story short, I am ready to fire up my motor in my '85 TransAM with a modified VX LS1 harness and PCM, but there is no spark and no fuel.
Everything else on the PCM checks out, VATS removed, turn ignition and fuel pump primes, turn the key and the engine cranks, but the PCM isn't receiving the cranking signal.
I did a check and the Crank sensor (Vortec L31 type) is getting 12v and ground, but the signal wire is putting out a constant 1.30v DC regardless of reluctor wheel position, or even when its removed from the hole.
From what I've read online, this sensor should only output wither 5v or 0v is this correct?
Its a brand new sensor from EFIConnection so I wouldn't expect it to be faulty, but its the only explanation I can come up with.
Here's the reluctor wheel alignment, does this look right?
![Name: temporary_210.jpg
Views: 477
Size: 209.8 KB](https://ls1tech.com/forums/attachments/pcm-diagnostics-tuning/630304d1501433929-crank-position-sensor-problem-temporary_210.jpg)
#3
On The Tree
Thread Starter
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Yep, 12v at PCM power pins and 12v at crank sensor power pin when cracking, it's just putting out a constant 1.30volts from the signal wire.
I'm 100% confident now that its the crank sensor, as 1.3v should not be possible when its working, it would either be 0v or 5v.
I'm 100% confident now that its the crank sensor, as 1.3v should not be possible when its working, it would either be 0v or 5v.
Last edited by evilstuie; 05-31-2016 at 02:24 PM.