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Name is Nick from Los Angela’s CA. Also a Marine Veteran, Semper Fi to any other Jarheads in here. This is my wife’s daily driver, she has had this vehicle before I came in the picture, it was maintained well but there were some issues that I fixed to get her back and healthy. Was going to sell it, but after the work been put into it, it’s a hate/love with it now, so she is staying. Premium 06 Automatic Mustang GT 4.6L 3V W/ the MyColor 6 Gauge Instrument Cluster with 126K.
Vehicle is stock besides suspension, and aftermarket radio.
I am currently having a Fuel Gauge problem either at the Instrument Cluster, Sending Unit, or anything that is connected to this electrical.
So before the issue I will discuss, I had the issue of not being able to fill the gas past half tank, it would shut off. I fixed that issue, with replacing the Evap Canister, Evap Valve, Evap Purge Solenoid. Now after replacing these parts, there was no longer a fuel fill up issue. I know ran into the issue of a Low Fuel Indicator at Half Tank. The Fuel Gauge would drop to E and the Mileage Indicator would change to 5 miles or 17 miles till empty. I knew this had to be false, the wife actually ran out of gas. So I then replaced the Fuel Pump Module/Sending Unit on the D/S. It seemed to have worked, but then again it happened. So for the past month now we have been ensuring to stay above half tank lol. There are no DTC Error Codes that show up now though, no check engine light, just the low fuel warning, and it will correct itself after a couple seconds.
I started to do a little diagnosing, and see maybe if there was an issue with the Gauge. I tried to enter HEC Dealer Mode, and it partially works. It skips the entire tEST and does not do any Gauge sweep. Upon holding the Reset and Select button and then turning ignition to On it will go straight to Rom Level 1, Boot Level 1, Final Date, Serial Number, Display Test (But no test is displayed), and then 30 Green Squares, Obtain IC Data, Continuous DTC None. That is all it will allow me to do.
Is it possible that the instrument cluster is bad because of this and therefore giving a false reading on the gauge and electronic mileage? Is it possible that the Fuel Pump Driver Module is faulty but allowing the parameters of still sending power to the pump and allowing it to function properly still? Could the INFO SELECT AND RESET button be faulty causing an error to occur within the system? Is it possible that the P/S Sending Unit is faulty and giving incorrect info? I have checked and have found no blend fuses in the engine compartment, as well as in the Smart Junction Box.
Also if anyone has any schematics of the ground wires, and where I should start checking first, by all means please. I am all ears at this point.
I just want to make sure I’m covering the right steps and making sure everything is all good before having to move that **** lock ring again on the pump.
Sorry for the long post, any other info needed to fix this problem, please let me know. Thank you. 🙌
As far as 'could the instrument cluster be bad', yes, it certainly could be. The better idea is to get the Ford or equivalent scan tool and try to diagnose it with that. Otherwise you're spitballin' on all of the things, including that fuel sender problem. The scan tool will tell you what the computer sees versus what the instrument cluster is saying.
The 2006 Mustang (well, pretty much all 2005+ Mustangs, not sure about 2004 and back) use the Instrument Cluster as a passthrough/coupler type thing between the ECU and the rest of the car, so it's kind of important to have it working right. Which is why I'm pointing you towards a proper scan tool diagnostic, as trying it old school is probably not gonna get to where you need to be/go. I dare say you're correct in the diagnosing of the cluster being bad, but one should be absolutely sure before spending time/money on that and it not be the problem. Could also be a wiring issue, connector issue, or perhaps unrelated but affecting issue like a corroded Smart Junction Box causing the CAN Bus to be having issues, that kind of thing.
And correct I need to get a code reader first, most def.
Hypothetically, if the instrument cluster was bad, and wanted to upgrade to a newer year cluster with the MyColor options. Would there be any issues with the install besides having it programmed? Or can you only use the 05-09 Clusters?
Last edited by ncgarner2006GT; 9/21/21 at 08:09 PM.
You can get the Mycolor 05-09 clusters and they can be programmed in, although there may be a switch on the center stack that also needs gettin'. Can't say for the 10+ ones, but I'd probably just not. Wanna say someone did it, but... I just wouldn't, a step a little too far for me on that kind of device.
Just wanna clear this one up, given the situation: You don't need a code reader. You need a scan tool. Way different tool. You can get a code reader if you want, but in this case I fear it will not do the job of getting you proper information to correctly solve the problem. I can't say which scan tool will do the job except the actual Ford one at a dealership. You can try (at multi-dollar expense I'm sure) other scan tools from, say, Autel or Snap-On, or you can look into the freemium Forscan software and get the recommended OBDII cable they want to use and see if that doesn't do it. No guarantees, but they have a forum and you can ask there about this maybe...?
These computerized cars are complicated and almost require a computer, electrical AND mechanical technician, either separately or rolled into one, just to keep them running. Which is what they want, either spend the money on them to fix it, or spend the money on a new one. Ain't like them carburetor cars anymore.
9/21/21, 06:18 PM
I just wouldn't, a step a little too far for me on that kind of device.
"What They Said!
