Help: 02 DIC Fuel Economy Problem

[niteflite1287]

So I did the DIC upgrade off of a denali this weekend on my truck and it seems to be working except for the MPG function which is either -- or 0. Ive put about 50mi at most since I installed it. I get fuel tank range fine...or least something that seems reasonable that is slowly going down. Any ideas?

 

[DAVe3283]

I would guess you are running a 2002 OS on your ECU? Since the '01-02 trucks didn't have a DIC, I don't think the ECU reports fuel use to the data bus.

You could try upgrading to a 2003 OS on your ECU and see what happens.

Out of curiosity, what did the Denali DIC look like for the 2002? Or is it just like the '03-07 cluster? ...er, I mean, a photo of the MPG function showing "0" might help us diagnose things, yeah, that's it!

 

[niteflite1287]

thats not my install, but its the exact same unit. and yes i'm running the 02 OS an early version if i'm not mistaken, I need to flash it if I can find someone with the appropriate tools. :hug:

 

[DAVe3283]

Wow, fancy! Does yours display the day & date too? Cause this is nice. My factory NAV says the date, but not the day (I always forget what day it is, go figure), so I am jealous.

I'd try a 2003 OS and see what happens. Anyone with EFILive can flash it, but they'll need a VIN license ($99). But you can probably get them to throw a decent tune on there while they're at it!

 

[niteflite1287]

yup buts its in a not so fancy mount right now made from ducktape in my overhead...oh well...at some point i will pull make the mount.

 

[paoutdoorsman]

Interesting. As far as fuel usage being reported to the bus, it just may be. I have a ScanGauge II in my 02 and it provides all fuel/trip related information.

Tell me more about the Denali DIC upgrade. Please?

 

[niteflite1287]

Basically the DIC which was included with a denali or escalade can be plugged into the data bus of our trucks...its quite simple and i can provide wiring schematics if you would like. It taps off of the class two splice pack to the left of the steering column and the speed signal on the mebec. The dic is the in theory capable of providing instantaneous and avg mpg. It also provides a daily, annul mileage log and two trip counters, a time and the range based on available fuel plus the date and time. It cost me about 50 or so to get one on ebay and then just my time and some 18ga wire to install it. I installed mine in the overhead console as it seemed the most reasonable place. The OEM location is in the lux console which I don't have.

 

[DAVe3283]

Oh, this made me think: does the trip meter work on it? Because if it didn't have a working speedometer input, it couldn't calculate MPG.

If it does, than ?????? Maybe double check the data bus connection?

Hopefully you get it working right, it is really slick to have the instant MPG. Probably the most used display on my DIC.

 

[niteflite1287]

hahah i was thinking the same tonight actually...it still doesn't work. right. the funny thing is it looks like it had both working inputs before b/c it gave an average mph along with the trip distances. However when i was doing some work at the Relay Body Block tonight i found the speedometer input splice had been broken. chance are the electrical tape was holding it kinda together. So i fixed that but didn't get a chance to test drive the truck (its 2am and i have to be to work by 6) so well see. (ya it was one of those oh i'll go work on the truck for like 30 mins after dinner....wtf its midnight nights). I figured the serial data has gotta be working since it was displaying range and that wouldn't be possible without a bcm/ecm input.

 

[DAVe3283]

Well, hopefully that's all it is. Let us know!

And I know exactly what you are talking about regarding time disappearing while working on the truck. That happens to me way too often. But hey, that's what caffeine is for!