Wiring & PCM Question

CODE4LS1 · 08-07-2009, 11:38 AM

Got my harness installed yesterday and it fit PERFECTLY! Thanks Jared!

However when I tried to start it it died right away and does so every time I start it. How do I relearn the theft deterrent so the BCM and PCM communicate?

When the key is on, the reverse lights stay lit no matter where i position the PNP switch on the side of the trans. Is this still a prob with the PNP? Once I take it out of park the reverse lights go out.

Also the fuel guage does not respond

My HP Tuners will not connect nor will it scan. It fails immediately at "Unable to read PCM". I know this is not wiring related (hopefully), but is there some things to check so I can read my PCM?

Thanks in advance......I know my questions are not strictly related to the wiring harness, just thought I would pick your brain if you had any suggestions for me.

Daniel

CODE4LS1 · 08-07-2009, 03:02 PM

I mis-connected wire labeled #11 to pin #10. Once I did that I was abe to read the PCM with no troubles.

I still have a problem with a dead fuel gauge and back up lights remain on. Anyinsight on that?

***CPWire*** · 08-08-2009, 08:51 AM

What kind of program are you starting with in the computer?

CODE4LS1 · 08-08-2009, 03:12 PM

My apologies. I forgot to update the thread last night. After I got it running the fuel gauge started working, but the back up lights remain on.

I'm using a stock '99 Silverado PCM.

CODE4LS1 · 08-10-2009, 11:29 PM

Ok, I changed the PNP switch and the backup light remain on while in park. Is there poss. some reversed wires in the connector that need switched back? If so, which ones?

Also, do you have a PN# for a radiator cap on your AFCO radiators? My stock replacement one does not seem to be building pressure.

Thanks!

***CPWire*** · 08-11-2009, 08:26 AM

Can you unplug the PNP switch and turn the key on to see if the backup lights come on without the switch even plugged in?

On the rad caps, I usually just go over to AutoZone and pick up a polished one from Spectre

CODE4LS1 · 08-11-2009, 11:40 AM

Ill go unplug the PNP switch to see what happens and get a cap from Autozone. Thanks!

CODE4LS1 · 08-11-2009, 07:43 PM

Ok, I unplugged the PNP switch and turned the key on and no reverse lights. What should I do?

Also, the gear indicator in the IC seems to be very slow reacting to my gear inputs, sometimes not even highlighting the appropriate gear I'm in. Any suggestions?

***CPWire*** · 08-12-2009, 08:18 AM

Sounds like something is out of whack with that Park Neutral switch maybe.
When you can be with the truck, and check some things out with me on the phone at the same time, give me a call. It would be quicker and easier to just walk through some checks over the phone and see what is happening that way.

CODE4LS1 · 08-12-2009, 02:57 PM

Thanks Jared, I'll give you a call hopefully by the weekend before you close so we can straighten it out. I have a busy schedule th rest of this week but I think I should be able to give you a shout tomorrow.

Thanks again.

08-07-2009, 11:38 AM	#1
CODE4LS1 Registered User Join Date: Feb 2009 Posts: 513 Location: Issaquah, WA User is: OffLine	Wiring & PCM Question Got my harness installed yesterday and it fit PERFECTLY! Thanks Jared! However when I tried to start it it died right away and does so every time I start it. How do I relearn the theft deterrent so the BCM and PCM communicate? When the key is on, the reverse lights stay lit no matter where i position the PNP switch on the side of the trans. Is this still a prob with the PNP? Once I take it out of park the reverse lights go out. Also the fuel guage does not respond My HP Tuners will not connect nor will it scan. It fails immediately at "Unable to read PCM". I know this is not wiring related (hopefully), but is there some things to check so I can read my PCM? Thanks in advance......I know my questions are not strictly related to the wiring harness, just thought I would pick your brain if you had any suggestions for me. Daniel
	[Reply w/Quote]

08-07-2009, 03:02 PM	#2
CODE4LS1 Registered User Join Date: Feb 2009 Posts: 513 Location: Issaquah, WA User is: OffLine	Re: Wiring & PCM Question I mis-connected wire labeled #11 to pin #10. Once I did that I was abe to read the PCM with no troubles. I still have a problem with a dead fuel gauge and back up lights remain on. Anyinsight on that?
	[Reply w/Quote]

08-08-2009, 08:51 AM	#3
*CPWire* Makin Sparks Age: 31 Join Date: Jun 2002 Posts: 1,265 Location: Hudson, Florida User is: OffLine	Re: Wiring & PCM Question What kind of program are you starting with in the computer?
	[Reply w/Quote]

08-08-2009, 03:12 PM	#4
CODE4LS1 Registered User Join Date: Feb 2009 Posts: 513 Location: Issaquah, WA User is: OffLine	Re: Wiring & PCM Question My apologies. I forgot to update the thread last night. After I got it running the fuel gauge started working, but the back up lights remain on. I'm using a stock '99 Silverado PCM.
	[Reply w/Quote]

08-10-2009, 11:29 PM	#5
CODE4LS1 Registered User Join Date: Feb 2009 Posts: 513 Location: Issaquah, WA User is: OffLine	Re: Wiring & PCM Question Ok, I changed the PNP switch and the backup light remain on while in park. Is there poss. some reversed wires in the connector that need switched back? If so, which ones? Also, do you have a PN# for a radiator cap on your AFCO radiators? My stock replacement one does not seem to be building pressure. Thanks!
	[Reply w/Quote]

08-11-2009, 08:26 AM	#6
*CPWire* Makin Sparks Age: 31 Join Date: Jun 2002 Posts: 1,265 Location: Hudson, Florida User is: OffLine	Re: Wiring & PCM Question Can you unplug the PNP switch and turn the key on to see if the backup lights come on without the switch even plugged in? On the rad caps, I usually just go over to AutoZone and pick up a polished one from Spectre
	[Reply w/Quote]

08-11-2009, 11:40 AM	#7
CODE4LS1 Registered User Join Date: Feb 2009 Posts: 513 Location: Issaquah, WA User is: OffLine	Re: Wiring & PCM Question Ill go unplug the PNP switch to see what happens and get a cap from Autozone. Thanks!
	[Reply w/Quote]

08-11-2009, 07:43 PM	#8
CODE4LS1 Registered User Join Date: Feb 2009 Posts: 513 Location: Issaquah, WA User is: OffLine	Re: Wiring & PCM Question Ok, I unplugged the PNP switch and turned the key on and no reverse lights. What should I do? Also, the gear indicator in the IC seems to be very slow reacting to my gear inputs, sometimes not even highlighting the appropriate gear I'm in. Any suggestions? Last edited by CODE4LS1 : 08-11-2009 at 07:45 PM.
	[Reply w/Quote]

08-12-2009, 08:18 AM	#9
*CPWire* Makin Sparks Age: 31 Join Date: Jun 2002 Posts: 1,265 Location: Hudson, Florida User is: OffLine	Re: Wiring & PCM Question Sounds like something is out of whack with that Park Neutral switch maybe. When you can be with the truck, and check some things out with me on the phone at the same time, give me a call. It would be quicker and easier to just walk through some checks over the phone and see what is happening that way.
	[Reply w/Quote]

08-12-2009, 02:57 PM	#10
CODE4LS1 Registered User Join Date: Feb 2009 Posts: 513 Location: Issaquah, WA User is: OffLine	Re: Wiring & PCM Question Thanks Jared, I'll give you a call hopefully by the weekend before you close so we can straighten it out. I have a busy schedule th rest of this week but I think I should be able to give you a shout tomorrow. Thanks again.
	[Reply w/Quote]