L29 0411 Swap - Struggling with crank relearn and P0300

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eran tomer

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The PRNDL doesn't provide voltage. The PCM is looking for an active ground. A 95 would have the PRNDL switch running to the cluster, but not the PCM so you will need to splice something in to those existing wires to get the active ground signals to the 0411 if you want them there.
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this is the 95 diagram. I totally don't understand it. what are the 4 ranges and and what's the parity shmarity? and how does it show 7 positions on the cluster?
I was thinking that those 4 wires should light a grounded test bulb between the cluster and the tranny but no.
 
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Supercharged111

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this is the 95 diagram. I totally don't understand it. what are the 4 ranges and and what's the parity shmarity? and how does it show 7 positions on the cluster?
I was thinking that one of those 4 wires should light a grounded test bulb when P or N is selected.

Just as vague as the blinker schematics I find for my Corvette.
 

BeXtreme

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this is the 95 diagram. I totally don't understand it. what are the 4 ranges and and what's the parity shmarity? and how does it show 7 positions on the cluster?
I was thinking that those 4 wires should light a grounded test bulb between the cluster and the tranny but no.
No, those three switches and the parity switch all provide grounds depending on the position of the switch. So in Park you might have "A" and "Parity" providing ground and in Neutral you might have "A" providing ground, but "Parity" is an open. The "PRNDL Module" inside the cluster is a "black box" and you have no visibility on what it is doing or looking for. The cluster gets power in from that fuse and then it has pull up resistors and power on pin 9,10,11, and 12 at the cluster. When the PRNDL switch moves positions, it will provide ground on one or all of those pins in order to tell the module in the cluster what position it is in. You can splice a wire straight from there into the same labeled pins on the 0411 in order for it to be able to tell what position the shifter is in. You can find the connector pinouts here: https://lt1swap.com/99-02_vortec_pcm.htm
The transmission pins are highlighted in Red. The easiest would be to just splice into the wires right next to the cluster and run 4 wires from there to the 0411 pins listed. The schematic you posted already lists the wires with the same name that the 0411 pinout uses.. so it's a piece of cake. You will have PRND A, B, C, and P.
Just as vague as the blinker schematics I find for my Corvette.
Seems pretty specific to me. Anyone with a basic knowledge of automotive electrical should be able to use that schematic to troubleshoot their system pretty easily. It would be nice if you could see the expected behavior of the PRNDL module as well, but I would bet it is a digital circuit board and you wouldn't be able to do anything with it even if they provided that info. It's either going to work right with the provided inputs, or not.


Here's the logic for the PRNDL switch position just in case this helps you in some way. Just to be clear, HI/LO isn't really accurate here unless you are back probing the connector on the cluster module or switch or at the 0411 connector once you have spliced in. That's because the voltage is being supplied by the cluster and the switch is grounding it. If the connector on the cluster is disconnected, then you would test it on OHMS and see it as an open or continuity to ground instead of voltage or no voltage. In that setting HI=open and LOW=<2 Ohms
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Supercharged111

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Seems pretty specific to me. Anyone with a basic knowledge of automotive electrical should be able to use that schematic to troubleshoot their system pretty easily. It would be nice if you could see the expected behavior of the PRNDL module as well, but I would bet it is a digital circuit board and you wouldn't be able to do anything with it even if they provided that info. It's either going to work right with the provided inputs, or not.

It totally leaves you hanging as to what A, B, C is. Looking at the switch again after some coffee that's clear now.
 

eran tomer

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so if I test for voltage with a test bulb either wire somewhere after the cluster as in the picture it won't lit the bulb? should I test ground by checking for continuity between the wire and ground?

I have a single wire with the psi harness that needs to be grounded when in N or P so I wouldn't run additional wires to the pcm pins.
 
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BeXtreme

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so if I test for voltage with a test bulb either wire somewhere after the cluster as in the picture it won't lit the bulb? should I test ground by checking for continuity between the wire and ground?

I have a single wire with the psi harness that needs to be grounded when in N or P so I wouldn't run additional wires to the pcm pins.
You aren't going to get enough amperage through there to light up a test light in most situations due to how those circuits work. If you put a multimeter on it, it will show voltage.. but probably not 12v. It won't allow enough current to flow through there to light up a bulb either... at least I would think not. I'm still not sure what you are actually trying to do here... you know all of those wires work correctly because your cluster shows the right gear. You can splice in and run all of the wires to the right spot on the 0411, but it sounds like you got the harness set up for a single wire NSS and your PCM is likely programmed as such. There is no wire on the PRNDL that will only be grounded when the trans is in N. I believe there might be a NSS on the column though...
Otherwise I would suggest picking off the parity wire. That would give you active low in P/N but not in Reverse or OD. You would also signal it as being in Neutral when in D3 or D1, but that's much less likely to be an issue I think.
 

eran tomer

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I'm still not sure what you are actually trying to do here... it sounds like you got the harness set up for a single wire NSS and your PCM is likely programmed as such.
correct. they ask to ground a single wire from the pcm when in P or N.

I found a green wire on the c200 connector that gets voltage when in P, so I can use a relay to ground that pcm wire. I still remain with the N problem.
 
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