PCM help please!

[Jlan87]

I have an 04 Yukon xl 5.3 vortec with the flexfuel. 

i am new to the site so I’m hoping I am posting this is the right spot, a month back I started getting a very slow startup. I replaced battery and had a code for the camshaft positioning sensor so I changed that and then one day just did not start. Crank and crank but no fire. 
 

after trying some different things it would start but was dumping fuel smoking heavy. I had tested my voltage at my camshaft sensor and wasn’t getting what I needed so I went to the pcm and the output wasn’t what I needed pulled the plugs and they were corroded all nasty and dried out. So I cleaned off the plugs and stems on the pcm put some grease on and it ran just fine for about a week then did the whole thing again. 
 

I ended up going to a junkyard and yanking some old plugs and I butt connected new tube pins on the wiring harness plugs. I’m doing so I am not %100 positive I have two of the four wires back in the right spot in the plug. I have a new PCM on the way but I am nervous if I plug it in and try and fire it up if it’s hooked up wrong in the wiring harness will it fry it right off the bat? Or should I just get a new wiring harness as well? 
 

any help would be appreciated. Even if it’s just telling me if I am posting in the wrong spot. Thank you looking forward to being a member I love my GMCs

[swathdiver]

What is your fuel pressure with the key on and at idle?  Does it hold for 5 minutes before bleeding down?

[Jlan87]

10 minutes ago, swathdiver said:

What is your fuel pressure with the key on and at idle?  Does it hold for 5 minutes before bleeding down?

 

It hasn’t been anything with the fuel, the PCM wasn’t giving the right message to the camshaft sensor so that’s why it was burning. When I cleaned it up it ran fine then corroded again so I replaced the pins on the wiring harness just not sure if they’re all back in the right spot. Don’t want to fry a brand new pcm 

[newdude]

What connector to the PCM did you have the pins out of?  If you can give the color of it or which position it plugs into on the PCM.

 

Also, new PCM wont run the truck unless its been programmed.    

Edited July 11, 2020 by newdude

[redvett]

Did your relearn?

 

Do you have to relearn a crankshaft position sensor?

A crankshaft variation relearn must be performed if: A diagnostic trouble code of P1336 is present. ... If there is any power train trouble code other than P1336 (Crankshaft Position Variation not learned), the computer will disable the relearn function until the problem that caused the code has been eliminated.

[Jlan87]

4 hours ago, newdude said:

What connector to the PCM did you have the pins out of?  If you can give the color of it or which position it plugs into on the PCM.

 

Also, new PCM wont run the truck unless its been programmed.    

I’m getting a programmed one. I removed three. Camshaft sensorfuel pump sensor and airflow sensor because the pins for those were nasty. Two of them are white. And I didn’t mark which went where. 

[Jlan87]

4 hours ago, redvett said:

Did your relearn?

 

Do you have to relearn a crankshaft position sensor?

A crankshaft variation relearn must be performed if: A diagnostic trouble code of P1336 is present. ... If there is any power train trouble code other than P1336 (Crankshaft Position Variation not learned), the computer will disable the relearn function until the problem that caused the code has been eliminated.

I didn’t relearn anything but when I changed the camshaft sensor and mass air flow and the pins everything was fine and the codes were gone for about 3 weeks

[newdude]

On 7/11/2020 at 4:27 PM, Jlan87 said:

I’m getting a programmed one. I removed three. Camshaft sensorfuel pump sensor and airflow sensor because the pins for those were nasty. Two of them are white. And I didn’t mark which went where. 

 

I narrowed down to ones that it sounds like you removed.

 

Quote

 

Table 1:	Powertrain Control Module (PCM) C1
Table 2:	Powertrain Control Module (PCM) C2

Powertrain Control Module (PCM) C1

BLUE CONNECTOR
Function
56	WHT	1579	Fuel Temperature/Composition Signal (L59)
73	BRN/WHT	633	CMP Sensor Signal

Powertrain Control Module (PCM) C2

GREEN CONNECTOR
3	TAN	1465	Fuel Pump Relay Control - Secondary (Dual Tanks)
9	DK GRN/ WHT	465	Fuel Pump Relay Control - Primary
31	YEL	492	MAF Sensor Signal
54	PPL/WHT	1589	Fuel Level Sensor Signal - Primary
64	DK GRN	890	Fuel Tank Pressure Sensor Signal (EVA)
73	DK BLU	1936	Fuel Level Sensor Signal - Secondary

 

 

[Jlan87]

13 hours ago, newdude said:

 

I narrowed down to ones that it sounds like you removed.

 

 

 

Fan****ingtastick. I will update when I use this

[sefiroxx]

Did you replace the cps harness as well?

[Jlan87]

On 7/14/2020 at 5:58 PM, sefiroxx said:

Did you replace the cps harness as well?

Idk what that is

[Jlan87]

On 7/13/2020 at 7:58 AM, newdude said:

 

I narrowed down to ones that it sounds like you removed.

 

 

I removed the 43 44 45 46 48 Nd 51 from the blue connecttor

[Jlan87]

Ok so everyone can see I replaced the pins on 43 44 45 46 48 and 49. Everything is in the right spots and The three grays which I wasn’t sure if the placement are just 5 volt reference which they all three give 5 volts so should it matter which one they are plugged into?

[newdude]

20 hours ago, Jlan87 said:

Ok so everyone can see I replaced the pins on 43 44 45 46 48 and 49. Everything is in the right spots and The three grays which I wasn’t sure if the placement are just 5 volt reference which they all three give 5 volts so should it matter which one they are plugged into?

 

 

The 5V references, #46, 46 and 48?  I'm pretty sure it will matter?  Each ref. line is for a specific component or possibly components.  

 

 

Pin 45 5v line, circuit 2700 is for the refrigerant pressure sensor, from that sensor to the PCM.  

 

 

 

Pin 46 5v line, circuit 474 is for the fuel tank pressure sensor to the PCM.

 

 

 

Pin 48 5v line, circuit 597 is for the MAP sensor to the PCM.