How to: Install DIC in gmt400 overhead console

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lxe4

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I guess I can live without all the real neat stuff. I have a metric/on of unit as well. It uses less wiring that I already have in place, and im hoping I can piggyback the temp circuit to the trans sensor anyway
 

lxe4

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ITS VEEERKING!! so, tried another computor from some scrap truck I raided from the car dump on the rez I was working on last summer that I planned to turn into blackbear as a core. I honestly don't remember what the truck was. Must have had a 4l80 because it drives just fine. ALSO makes my DIC work! Has completely different part numbers on it than my original, which also has different numbers than the blackbear that I have. also messed with my steering today to get some tightness back in it. Big wins for Alex today!!
 

lxe4

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the dirty one is the random junker unit and the cleaner one is the original factory delivered unit from my truck. numbers dont mean anything to me but perhaps helpfull to others
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_nickjoseph

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WE HAVE COME TO THE CONCLUSION THIS DOES NOT WORK ON DEISELS

What you need.
-DIC out of a blazer, a long console DIC has the compass built in
-wire of your choice (I used 6 conductor phone wire)
-temp sensor
-I used 7 feet of wire from DIC to Radio I would suggest using about 8 feet
-9 feet of wire to the temp sensor


Ok here is how I did it.

I started by removing the screw on the front of the OHC so I could slide it forward to release it from the roof
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then unplugged the connector for the lights.

I then had to make my own wireing harness for it because I did not want to even try to get the factory one from the blazer.
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If you make your own harness make sure you take notes as to what wire colors go where.
I soldered all of my connections but if you don't know how or are no good at it you can use crimp conectors , but you have to make sure your connections are flawless.

Then take the dash panel off so you have acesss to the radio wires, and remove your radio.
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I ran the wire on top of the headliner and down the drivers side A-piller into the dash by the headlight switch under the cluster and then to the radio(most of your wires will be here.
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The wires you need at the radio are as follows
Pin #6 ppl/white------>LED dimmer
#11 grey------>Illumination circut power
#9 drk green---------> RAP fuse supply
#16 drk green/white ---------->VSS


I used the power and ground from the lights in the OHC.

The only wire needed out of the cab is the signal wire for the temp sensor. (lt. green/black)
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I tested the DIC before the temp sensor and the class 2 serial wire was hooked up thats why it reads (--)
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I put a piece of wire loom over the temp sensor so it wasn't easily seen behind the grill
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This is where I mounted the temp sensor using the factory clip from the blazer
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And this is where you hook up to the class 2 serial data
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Some finished pics.

Compass was not calibrated yet

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I have not figured out why the range mode always reads Lo

EDIT: I found out that for the RANGE mode to work the fuel level sender has to run thru the computer (96-97 does not) 98+ does.

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This is the only in operation pic I have
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What is
WE HAVE COME TO THE CONCLUSION THIS DOES NOT WORK ON DEISELS

What you need.
-DIC out of a blazer, a long console DIC has the compass built in
-wire of your choice (I used 6 conductor phone wire)
-temp sensor
-I used 7 feet of wire from DIC to Radio I would suggest using about 8 feet
-9 feet of wire to the temp sensor


Ok here is how I did it.

I started by removing the screw on the front of the OHC so I could slide it forward to release it from the roof
You must be registered for see images attach

then unplugged the connector for the lights.

I then had to make my own wireing harness for it because I did not want to even try to get the factory one from the blazer.
You must be registered for see images attach

If you make your own harness make sure you take notes as to what wire colors go where.
I soldered all of my connections but if you don't know how or are no good at it you can use crimp conectors , but you have to make sure your connections are flawless.

Then take the dash panel off so you have acesss to the radio wires, and remove your radio.
You must be registered for see images attach


I ran the wire on top of the headliner and down the drivers side A-piller into the dash by the headlight switch under the cluster and then to the radio(most of your wires will be here.
You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach


The wires you need at the radio are as follows
Pin #6 ppl/white------>LED dimmer
#11 grey------>Illumination circut power
#9 drk green---------> RAP fuse supply
#16 drk green/white ---------->VSS


I used the power and ground from the lights in the OHC.

The only wire needed out of the cab is the signal wire for the temp sensor. (lt. green/black)
You must be registered for see images attach


I tested the DIC before the temp sensor and the class 2 serial wire was hooked up thats why it reads (--)
You must be registered for see images attach

You must be registered for see images attach


I put a piece of wire loom over the temp sensor so it wasn't easily seen behind the grill
You must be registered for see images attach


This is where I mounted the temp sensor using the factory clip from the blazer
You must be registered for see images attach


And this is where you hook up to the class 2 serial data
You must be registered for see images attach


Some finished pics.

Compass was not calibrated yet

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

I have not figured out why the range mode always reads Lo

EDIT: I found out that for the RANGE mode to work the fuel level sender has to run thru the computer (96-97 does not) 98+ does.

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach



This is the only in operation pic I have
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What is the name of the temp sensor we need to do this?
 

_nickjoseph

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This is all I’m getting on mine. Didn’t hook up the temp but every thing else is correct I’m sure

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Hobie

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This is all I’m getting on mine. Didn’t hook up the temp but every thing else is correct I’m sure

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DC means the temp sensor is disconnected, you must have a regular temp/compass DIC
 

Hobie

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i do I wanted the one that shows the mpg and all that good stuff so I’ll be headed back to get that one and a temp sensor
I have two DICs that have and two temp sensors (although a different style, but still work the same) that I am willing to part with. I'll retest everything before a final decision is made, if you're interested
 

_nickjoseph

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I have two DICs that have and two temp sensors (although a different style, but still work the same) that I am willing to part with. I'll retest everything before a final decision is made, if you're interested
Where u located? Mine only shows the direction but that doesn’t even work but I want the all function one for direction temp and the mpg and all that. I need a temp sensor and the plug for the dic
 

Hobie

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Where u located? Mine only shows the direction but that doesn’t even work but I want the all function one for direction temp and the mpg and all that. I need a temp sensor and the plug for the dic
I'm in Missouri, but can ship, I'll double check the DIC tomorrow morning to make sure the functions work correctly
 
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