Voltmeter inop w/EFILive tune in 4500 Topkick

[Looney-Tune]

Hello all, first post here, hope to do much more. Just received EFILive to custom-tune our project truck, a 2005 LLY GMC 4x4 4500 Topkick. Loaded the first tune from McRat, and noticed voltmeter was inop. Also had a P0562 system voltage low code set sometimes, but the batteries and charging system are fine. All other gauges work fine. Voltmeter works fine with stock tune. Any ideas? I'm working on some tunes for this beast, trying to work out the bugs. These medium-duty trucks are a different animal when it comes to tuning, unlike the light-duty d-maxes. The truck's running pretty good right now, made some sub 7 second 0-60 runs today with it. (Remember, it's an 11,200lb truck) This truck has all the goodies. Thanks,

Rich

[GMPX]

Rich, I suspect the modified tune file you have might not be 100% correct for the truck. Did you send Pat your stock tune to modify or was it one that Pat just sent to you?.

Cheers,
Ross

[Trippin]

I've seen this before when one of the segments is off. Open up your stock tune and then in a different window your modified tune.

On the calibration page compare each one of the segment numbers.

Once you have determined which one is incorrect, open up your modified tune and then use the compare feature to open up your stock tune as the ALT. tune

Go to the Edit menu and select "copy entire segment" and then select the segment that is incorrect. This will copy the segment from your stock tune into the modified tune.

[GMPX]

I would suggest the System segment is not matched.

Cheers,
Ross

[Looney-Tune]

Thanks guys, you were all correct. I re-loaded the mismatched segment values, and the voltmeter worked with the McRat tune, however, the truck ran like a dog. Apparently, there was some kind of mismatch with the actual data. Pat is sending me out a new tune with the proper segment values from my stock tune. I'll see how that works. Meanwhile, I'm continuing on with my own tune. I'm kind of stuck right now, because we installed Suncoast's 6 speed conversion, and I can't tune the TCM because it is locked by them. I understand why they do this, but now we must wait until they can re-flash our stock TCM and send it to us. There are some problems with this 6 speed conversion in the 4500. It just doesn't shift right, and you cant lock-out the overdrive anymore. More to follow.

Rich

[Trippin]

Try updating "only" the system segment. If you updated all the segments then you have returned your tune back to stock.