I will start by prefacing this with I have already done a P59 swap when I swapped electric fans into my truck. So this write up will be based on doing this with a p59 pcm swap. I do believe its possible to use a 0411 PCM for this but more reverse engineering of its operating systems and testing is needed. If that information is revealed to me I will update this post. What's already known about the 0411 is everything can work just without the volt gauge which more than likely can be enabled but I do not know for certain and I don't know what bytes to change to what. This is not the case with the P59 running the 7603 OS which is the go to OS for the P59 due to its amazing versatility and documentation.

If you want to swap the pcm to do this mod, I highly recommend getting an express van P59. Why? For one it has the IAC drivers so you can keep your drive by cable. Two it supports analog ac request unlike most p59s. I'm not going to go into detail about swapping to a p59 for right now, I might add more information about that at a later date. If you want more info about it I'm more than happy to give information. You are also going to need a computer, pcm hammer, universal patcher, and a hex editor, I use HXD. To use pcm hammer you will an obd2 dongle that's capable. OBDXpro I recommend but there's other options. And you can use this same dongle to use IPC hammer to flash calibrations (to do things like enable the SWC) onto the cluster you swap in, and reprogram the mileage to match your truck.

So I'm going to start out with repining the plug that went into your stock cluster. The newer clusters use the same plug but with a much different pinout. So I will attach both pinouts. I recommend repining this 1 wire at at time since GM will use the same color wire multiple times on the same plug. You are going to have some wires that are no longer needed for the new cluster, like the oil pressure switch wire, a couple of different power wires as the newer clusters only need a pink ignition wire and the orange 12v all the time. I will list the wires no longer needed when I have a little bit of time. I recommend taking 4 of those no longer needed wires and repurposing those to be the 4 pins for the steering wheel controls for the cluster. I have swapped an 03+ wheel into my truck already and there's plenty of writeups about it so not going to go too much into that, but I will give what I know about the steering wheel controls. The top controls are for the radio, I used with my aftermarket. Key goes to steering wheel control top wire that goes to all buttons, then other side is ground to work like a resistance ladder which is easily programmed into an aftermarket head unit. The bottom ones are bit a different and those are the ones for the cluster DIC. Each button gets its own individual key wire from the cluster plug, then pushing the button grounds it to the same wire as the illumination circuit ground for the steering wheel controls and is again independent from the top controls. Don't forget you need the SWC enabled on the cluster for it to work if you want it. This is enabled on any cluster by flashing the correct bin file to it.

After repining the plug, you'll likely notice the voltage gauge doesn't work neither does the oil pressure because the cluster on the 02 down did those internally and the new cluster did those over serial data which is what the next section will be about. P59 with the 7603 OS can enable both of those and it is known. The 0411 can have oil pressure activated through serial data using a corvette segment, but more testing needs to be done to find the voltage over serial data. I believe it to be possible due to the fact the battery light comes through the data line.

00-02 Cluster pinout, I believe 99 is the same but that airbag system communicates differently on that truck so there will be more hurdles for that year

03-07 classic cluster pin out.

 

How to Enable Oil Pressure and Voltage through the class 2 data line on a P59 running 7603
​

Ok so now you want to enable the last gauges to have the full working setup. It's pretty easy, swapping to a p59 I found to be a good amount of work but worth it. But from this point its not that hard.

Oil pressure will go through the dataline as soon as you give a p59 an oil pressure reading. To achieve this you will need to remove your old 1 wire oil pressure switch. I recommend spending the money to get the specialty socket as it makes life easier. In place of the 1 wire oil pressure switch, install a 3 wire sensor for an 03+ truck. I got the sensor and pig tail for about 15 bucks and its the same threads. All 3 wires to go into the p59 but once it can read those datalines the oil pressure gauge works.

Voltage over class 2 is even easier as all you need to do is modify the bin file for your pcm and flash it. in the 7603 OS you will need to open a hex editor, set the byte width to 18. Then you will find 5 bits in a vertical row that are all 38. This is them

You will want to change all 5 of those 38s to 3A. Make sure your replacing the byte because you can't change the file size on that flash at all. On HxD i will high light one at a time then replace. After those 5 bytes are changed to 3A and look like this, you cansave the bin file and flash it using pcm hammer.

one last little thing about swapping to a p59.the 7603 OS is an 04 OS and that year changed a lot about he fuel system including a ascending unit that works opposite from the previous years giving you an opposite fuel gauge. The simple fix is to go into this parameter in universal patcher

Then opening a compare bin from an 03 truck with a matching fuel tank capacity and copy that table which will restore proper function of the fuel gauge.

I will be adding more at a later time but my fingers need a break right now

 

Wiring diagram to show how 03 oil pressure sensor needs to be hooked up

 

Wow, a detailed and informative post on here for a change.

 

I've been waiting on this post...

Next do the P59 swap post pls

Fantastic job Autumn

 

I am curious if this would work for 99 without throwing an airbag light. I have the transistor mod done on my Denali cluster so that it works in the 99 but I am not sure if I could do that same mod on the 03-06 cluster.

Not sure if it would be worth repinning everything to only find out I'm shafted on the light. Maybe pull it out? Wouldn't be factory

 

I am curious if this would work for 99 without throwing an airbag light. I have the transistor mod done on my Denali cluster so that it works in the 99 but I am not sure if I could do that same mod on the 03-06 cluster.

Not sure if it would be worth repinning everything to only find out I'm shafted on the light. Maybe pull it out? Wouldn't be factory

If you have it to where the light doesn't come on in a denali cluster which off the top of my head is 01-02 then it should work. 03-06 airbag light works the same as 00-02. The cluster light is just a data line message.

Interesting fact though I'm an idiot that sometimes "accidently" doesn't wear my seatbelt and on the 02 cluster the seatbelt light would come off after a couple minutes. On the 06 it doesn't come off until it actually goes on.

 

My 06 Sierra the seatbelt light will go off after a while.

The way to get the airbag light to not show was put a transistor on the back of the cluster. I have no idea how someone found the pins to make sure that it worked like that though. Would have to dive back into it.

 

Interesting I need through more cluster bins then lol

I also should do a deep dive into the 99 airbag system because I would like to include 99s for this mod

 

I can send the writeup to you. I think the guy hosting it quit hosting it.

 

Please do

 

Sticking this thread. Good info.

 

Thank you, was gonna ask for that lol

Airbag Light Fix

He is hosting it still. My download of his page won't save the photos. I had them separately lol

 

My 02 has an escalade conversion, and the ONLY issues I have with mine is the fuel reading opposite,
And my digital AC has 2 temps, cold and hot. 90 is hot, and 89 and down is same as 60. lol

 

eeeeee

Thank you, was gonna ask for that lol

Airbag Light Fix

He is hosting it still. My download of his page won't save the photos. I had them separately lol

Uptdste: 04 and 05 confirmed to be same. can be done this way too. Can't promise 06 and 07 but I'd be shocked at this point if they were different

Edit: Looking at an 03 board a similar fix is definitely an option, I'd go as far as to say easier even. There is a spare pin terminal on the 03 cluster that can be used to incorporate pin a11 from the 99 cluster. We also aren't dealing with the airbag light being powered when the truck is off. its powered exclusively by ignition.

The other lucky break here is the led is resisted going to ground. So an easy way to do this would be to desolder the leds surface mount resistor. Solder one side of the resistor on the pad that goes to the LED but facing the opposite direction of the other pad to break that loop. Then you would run a jumper wire from the other side of the resistor, to the unused pin you decide to use on the 03 cluster. Then when you repin the 99 cluster harness, you would move pin a11 to the corresponding pin that you jumpered the resistor to.

If this is confusing or need more detail including pictures, give me a few days and I think I can provide that. Also since board revisions are different I can't promise it will be exactly the same for 04+ but I would honestly be shocked if it was different.

 

If you just did the 04+ fuel tank I wonder if that would fix that without the computer. I can't remember how you get it to read right when you do that swap in the first place though.

 

Edited

Would just need the 04+ sending unit if using the 99-03 or 99-03 sending unit if 04+ pump is used.

Wouldn't recommend that route because I had to essentially remove the bed to replace my bad fuel pump. Which also contains the sending unit

 

No the 04+ pump needs the 04+ tank is what I mean. 04 pump has a better fuel bucket to prevent starvation

 

@LsxAutumn Dragging this back up. Were you able to check into the 99 airbag system to see what would be needed to keep the airbag light from sticking on when doing the 03-07 cluster swap?

I'm bored and thinking about it.

 

little bit late to the forum but I was just wondering if it is possible to do this without swapping in a p59 and just repinning the harness ?

 

@Aland Repinning the harness no. You need to move traces on the circuit board as well

 

First time really getting into circuit boards but I have a soldering iron how difficult would it be ?

 

Soldering iron won’t do the job I don’t think. It is pretty hard