PCM Pin ???
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From: Roxana, IL
PCM Pin ??? I'm LS swapping my 2000 S10 2.2L with a 2004 Trailblazer 5.3L LM4 engine/transmission. I'm using a P59 green/blue PCM, A 2005 Silverado 5.3L L33 start-up tune & a new CPW(Current Performance Wiring) complete engine harness. I am also using a Complete Holley high mount accessory drive system with the Corvette spacing.
I'm working on the Alternator Light that stays on. The alternator came in the Holley accessory drive kit with a Lester Part # 8292N. It's a 3 wire set up and uses the serial data line to communicate with a solid state chip in the dash for turning the light on/off. This is the same as the OE 0411 blue/red PCM that came with my S10 that used PIN 59 of the C1 PCM connector. I have been told that the 2005 Silverado 5.3L tune I have is not compatible with the S10 dash, others say it doesn't matter.
First let me explain the way i see it so far.
Both the 0411 & the P59 PCM's have two class 2 serial ports(that I'm aware of). The current pin used is PIN 58 of the C1 connector. PIN 59 of C1 is serial data but not used here. The harness is pinned at the PCM like a 2004 Corvette. Holley say's that alternator is wired most like a 2004 Corvette & it's pinned like the wiring diagram and PCM pin out CPW sent me for the Corvette.
A buyer's guide listing doesn't show 2004 Corvette on that alternator, it did list a 2003/2004 Trailblazer & they use PIN 59 of the C1 PCM connector,.
A 2001-2003 S10 that uses a an 0411 or P59 PCM uses PIN 59 of the C1 connector.
What's the difference between PIN 58 & PIN59?
Why 2 different Class 2 Serial Data pins?
I'm working on the Alternator Light that stays on. The alternator came in the Holley accessory drive kit with a Lester Part # 8292N. It's a 3 wire set up and uses the serial data line to communicate with a solid state chip in the dash for turning the light on/off. This is the same as the OE 0411 blue/red PCM that came with my S10 that used PIN 59 of the C1 PCM connector. I have been told that the 2005 Silverado 5.3L tune I have is not compatible with the S10 dash, others say it doesn't matter.
First let me explain the way i see it so far.
Both the 0411 & the P59 PCM's have two class 2 serial ports(that I'm aware of). The current pin used is PIN 58 of the C1 connector. PIN 59 of C1 is serial data but not used here. The harness is pinned at the PCM like a 2004 Corvette. Holley say's that alternator is wired most like a 2004 Corvette & it's pinned like the wiring diagram and PCM pin out CPW sent me for the Corvette.
A buyer's guide listing doesn't show 2004 Corvette on that alternator, it did list a 2003/2004 Trailblazer & they use PIN 59 of the C1 PCM connector,.
A 2001-2003 S10 that uses a an 0411 or P59 PCM uses PIN 59 of the C1 connector.
What's the difference between PIN 58 & PIN59?
Why 2 different Class 2 Serial Data pins?
Thread Starter
TECH Enthusiast
Joined: Jan 2019
Posts: 677
Likes: 490
From: Roxana, IL
Your right they do and I'm told they are the same. Just one is faster.
Both PCM's have a C1 T58 & T59 class 2 serial data.
The S10's use C1 T59 for circuit 1049. T58 for circuit 710
The 2003/2004 Trailblazer 5.3L uses C1 T58 for 1049. T59 for circuit 710
I'm trying to find out what is the difference between the 2 serial data terminals? if they is any difference?
Both PCM's have a C1 T58 & T59 class 2 serial data.
The S10's use C1 T59 for circuit 1049. T58 for circuit 710
The 2003/2004 Trailblazer 5.3L uses C1 T58 for 1049. T59 for circuit 710
I'm trying to find out what is the difference between the 2 serial data terminals? if they is any difference?
The protocols between the various year S10's is differant, that is why not all year 2nd gen S10 dashes, don't interchange. You might also have to start with an S10 OS and swap out the engine modules, to get the shift indicator and gas gauge to work. It might also you to use a 2004 compatible cluster.
Thread Starter
TECH Enthusiast
Joined: Jan 2019
Posts: 677
Likes: 490
From: Roxana, IL
The protocols between the various year S10's is differant, that is why not all year 2nd gen S10 dashes, don't interchange. You might also have to start with an S10 OS and swap out the engine modules, to get the shift indicator and gas gauge to work. It might also you to use a 2004 compatible cluster.
As stated above the two serial data wires are backwards to the the 2000 S10. I'm curious if that could be the reason it's on. Do the 2 separate data pins have a different algorithm/protocol?
