Requesting guidance (No crank situation)

[Rollin254]

Hi All,


Can anyone please provide guidance on this situation?


I have a 1993 GMC c1500 with an existing 4l60e transmission (A/T) and I am swapping in a 2005 LQ9 from 2005 Chevy 1500.
Using Universal Patcher, Tuner Pro and PC Hammer
Hardware is a P01_P59 running OS 12592618.
VTD (VATS) is configured as 2 and Tuner is showing "Current value: 2 (Out of range) [02] [ Min: 0 Max: 1]"
I have tried settings 0 and 1 with out any luck.
Neutral Start Switch Equipped is checked (I have tried unchecking this).
4l60e does not have exterior Park Neutral safety switch. This resides under the dash on the steering column.
Clutch Switch Type is set to 0:Norm_closed_to_Grn (I have tried this as 2: NO SWCH).


I am starting to think that the VTD is not set correctly or there is another setting that is not allowing the engine to crank.
Also tried using modified OS 12587603 from 2004 but had the same results. Attaching my current bin file.


Here are some additional details.
I am not able to crank the engine. Battery is charged and cable to starter has 12Vs. The purple wire for crank signal to starter does not.
Traced the wires to the under hood fuse block, crank fuse has 12v, and pin 30 on starter relay has power, but relay does not switch power to pin 87,
ends up being the crank signal purple wire going to the starter.


I tried running a wire from the fuse block at C2 F11 (DK GRN Park Neutral wire Switch) through the firewall to the Park Neutral Safety Switch
under the dash on the steering column to the Light Green wire. This Wire is grounded when steering column shifter is in Park and key is run/crank. The other wire is light blue and has 12V when Key is in run/crank. If I run the light blue wire to pin 85 on the starter relay or at C2 D11, C2 D12, when I turn the key to run position the engine cranks over immediately without being in the crank position.


Also, Coil packs have power and ground does ohm out. The Injectors have power but do not receive the control signal (pulse) to fire. I used
Noid light to verify injectors are not firing.


This again leads me back to the PCM. Does anyone have any ideas?


Any help is greatly appreciated.

[ralmo94]

Just off the top of my head, vats, shouldn't keep you from cranking, just prevent firing up?
Maybe some can correct me if I'm wrong on that.

It sounds to me like something isn't wired correctly, on a 93 truck you should be able to crank from the key without a PCM even being installed, if you jump the starter with a hand switch, does it fire up?

I would use the stock file and use vats delete patch from universal Patcher for the vats.

[Rollin254]

Hi Ralmo94,

the engine does not start even if I jump or use a hand switch. The injectors are not firing. I was thinking it is a pcm issue. I will try the stock file with the vats delete patch and try that really quick.

[ralmo94]

Hope it works for you, if not, you may need to verify your wiring

[Rollin254]

Hi Ralmo94, you are right, it is a wiring issue. I took the purple starter wire coming coming through the firewall and connected with the purple starter wire from the fuse block. it was pinned to C2 block. I went to put the negative battery terminal on and it sparked. Now I am a bit lost as where the wiring issue could be coming from. There is only 3 wires coming out of the firewall that I need to use with the stock harness/fuseblock/PCM for the engine to run.

The purple starter wire from the firewall is hot all the time. I don't believe this to be correct. But I have not mucked with the ignition inside of the truck.
Or is this normal for a 93 GMC? Any ideas on what I am missing?


This is how it is currently wired from fire wall:
large Purple starter wire is pinned to C1 A3 in fuse block.
Large Pink wire ignition hot in run/start pinned to C1 A9 in fuse block
Large red - hot at all times pinned to A7 in fuse block.
small pink ignition hot in run/start -pinned in C1 C9

[ralmo94]

Was the truck operation before the swap?
If so, was the purple wire going to the starter?
Iirc in 93, the wire went right from the ignition switch to the starter solenoid without the fuse box

[Rollin254]

Yes the truck was running and the purple wire went from the ignition switch through the firewall directly to the starter. Any idea why the negative terminal would spark now?

[ralmo94]

So the starter wire is hot all the time? I would suspect a faulty ignition switch. Unless its hot after the relay, then I would suspect a sticky relay, they do stick sometimes.

Then of course there is the possibility that no one likes, that it is shorted with another wire making it hot.

You will have a small arc when you connect it usually. The thing is how small is the arc, is an interior light or something on? Maybe an underhood lamp?

[Rollin254]

the book I have says the starter wire is hot while cranking but that is not what I am observing. Maybe there is a wire short in the dash. I will have to look. The under hood lamp is powered off a junction block on the passenger side of the engine bay. Thank you for helping, I really appreciate it. I need to do some more investigating.

[ralmo94]

Yes the starter wire should definitely not be hot all the time, if you find it, I'll bet you also find the source of the arc. Hope it's an easy fix for you.

[Rollin254]

Quick update: this lead me to the ignition switch. Original to the truck and worked before the swap. I bought a new one and now able to crank engine with the key. Thank you for the help. I don’t think I would have checked the ignition switch.

I am still not getting injector pulse. Been doing research and discovered engine speed (RPM) is not logging in OBDII. I have a lot to check/verify with Crank/CAM position sensors, wiring and grounds. At least I am heading in a direction instead of being stuck. Thanks again.