Issue using AlfaOBD to recalibrate fuel gauge using VehConfig 3-Fuel Capacity (36-290)

[TH22]

I live in Australia

I have a 2022 DT 100 Limited and have replaced the existing 98 liter petrol (gasoline) fuel tank with a 3rd party 205 liter sized tank.

AlfaOBD showed that the default "VehConfig 3-Fuel Capacity (36-290)" was set to 98 Liters (as the tank capacity was originally 98 liters)

When I tried setting to 205 (to match the replacement capacity) I found that the fuel gauge appeared to work (i.e. showed full as the tank was full) but then would suddenly drop back to empty on the next “Ignition switch” cycle or when stopping then starting the motor. Also, the Range (distance to empty) value was blank or did not change from what it was originally when I started (550). When I tried all sorts of values (except 98) I had the same result.

However, when I used a value of 130, the gauge gave a “Low fuel” message and then the needle slowly rose back to full (where previously it always rose real quick). When the motor was started, the Range value (Distance To Empty) increased from 550 (when 98 is used) to around 680

Does anyone know why only the values of 98 and 130 "work" [except that the "gauge rate of change" and Range (Distance To Empty) are incorrect] or is there a number that equates 205 liters?

Thanks

 

[Brutal_HO]

On the HD trucks with 50 gallon tank, that is the max setting that will stick (190 liters) for the primary tank.

Might try 190 and check results.

FWIW, CC trucks have additional tank options which can also be enabled with AlfaOBD. A member on HDRAMS is building a 4500 that didn't originally come with the extra tank(s) and has it working.

 

[TH22]

Thanks, but 190 did not work
I have tried 98,120,130,140,160,169,170,180,190,198-205.
So far only 98 (original setting) and 130 work
Rgds TH22

 

[Brutal_HO]

I just did a quick search and see someone set it to 194.

I just looked at my BCM config and factory is set to 189

VehConfig 3:
Fuel Capacity (36-290L): 189.000 Liters

 

[TH22]

I just tried both (194 then 189) but neither worked so returned back to 130 (which works as previously described)

 

[Brutal_HO]

I just tried both (194 then 189) but neither worked so returned back to 130 (which works as previously described)

Did you put in the three 0's?

189.000

 

[TH22]

Did you put in the three 0's?

189.000

I tried including the ".000" but it made no difference (it gets added to the value you enter into the VehConfig 3-Fuel Capacity (36-290 L field). I am going to check all sizes from 131 onwards - so far today I have tried 170-178 and 180-205 before the battery charge level got too low (when trying to check 179). I am currently waiting for the battery recharge to finish

 

[TH22]

I have now tried tank size (in litres) of 98,120,130-205.
So far only 98 (original setting) and 130 work

I have seen mention of setting "ECUConfig 4: Fuel Capacity" in various "posts" but could not find it.

 

[Brutal_HO]

I have now tried tank size (in litres) of 98,120,130-205.
So far only 98 (original setting) and 130 work

I have seen mention of setting "ECUConfig 4: Fuel Capacity" in various "posts" but could not find it.

The only thing I see in my BCM under

ECUConfig 4:

Secondary Fuel Tank Capacity: Not Present​

 

[TH22]

Body Control Module Continental MY 2022
ECUConfig 4:
ECU Configuration 4 (0-3): 1.000
ERS Available: Yes
Rear Wheel Dually: No
Max Gear: Eighth Gear
Virtual Speedometer Units: Not Set
Speedometer Range Max Scale: Not Set
IPC Configuration Feature Present: No
PTO Present: No
Ambient Dimmer: No
Heated Seat Present: Yes
Split Shaft Present: No
Actual Gear Display: Yes
Fleet Vehicle Content: No
Manual Headlamp Leveling: No
Gear Shift Indicator: No
Service Interval: 20000 km and 730 days
Temperature Celsius for UK: No
Type of Gallons: U.K. Gallons
Tailgate Ajar Indication: Yes
Stop&Start Menu Present: Yes

 

[Brutal_HO]

Body Control Module Continental MY 2022
ECUConfig 4:
ECU Configuration 4 (0-3): 1.000
ERS Available: Yes
Rear Wheel Dually: No
Max Gear: Eighth Gear
Virtual Speedometer Units: Not Set
Speedometer Range Max Scale: Not Set
IPC Configuration Feature Present: No
PTO Present: No
Ambient Dimmer: No
Heated Seat Present: Yes
Split Shaft Present: No
Actual Gear Display: Yes
Fleet Vehicle Content: No
Manual Headlamp Leveling: No
Gear Shift Indicator: No
Service Interval: 20000 km and 730 days
Temperature Celsius for UK: No
Type of Gallons: U.K. Gallons
Tailgate Ajar Indication: Yes
Stop&Start Menu Present: Yes

Yes, there are many other values listed under ECUConfig 4:

However, we were discussing a fuel capacity setting so that's all I replied with.

It would appear in the 1500 BCM, that option isn't even present.

HD BCM
ECUConfig 4:
___________________
ECU Configuration 4 (0-3): 1.000
ERS Available: No
Rear Wheel Dually: No
Max Gear: Sixth Gear
Virtual Speedometer Units: Not Set
Speedometer Range Max Scale: Not Set
IPC Configuration Feature Present: No
PTO Present: No
Ambient Dimmer: No
Heated Seat Present: Yes
Split Shaft Present: No
Actual Gear Display: Yes
Fleet Vehicle Content: No
Manual Headlamp Leveling: No
Gear Shift Indicator: No
Service Interval: 20000 km and 730 days
Temperature Celsius for UK: No
Type of Gallons: U.S. Gallons
Tailgate Ajar Indication: No
Stop&Start Menu Present: No
Secondary Fuel Tank Capacity: Not Present
Manual DPF Regeneration Present: Yes

 

[TH22]

Thanks, I had assumed that is why you only provided the fuel related

I have compared both "complete" lists and see your transmission is a six speed (plus a couple of other small differences) where mine is an 8 speed

 

[Brutal_HO]

Thanks, I had assumed that is why you only provided the fuel related

I have compared both "complete" lists and see your transmission is a six speed (plus a couple of other small differences) where mine is an 8 speed

HD, HO/Aisin so yes, 6-speed.

In the HD, only the Hemi trucks get an 8-speed ZF. There's even a 6-speed Aisin option in the Cab&Chassis.

I also had to enable the "Actual Gear Display" as that wasn't enabled in the HD trucks by default for some strange reason though it was shown in the EVIC setup in the OM.

 

[Jimmy07]

I have now tried tank size (in litres) of 98,120,130-205.
So far only 98 (original setting) and 130 work

I have seen mention of setting "ECUConfig 4: Fuel Capacity" in various "posts" but could not find it.

I doubt this will do anything for you, but you can force ECUConfig 4 fuel capacity to show up if you go to alfaobd settings, check the box for “do not verify ecu”, and select MY2016 power net when you connect to the body computer.

But, the issue you’re having is probably the 1500 BCM is only capable of broadcasting the messages for certain fuel tank size numbers, and nothing is going to work over 130. The factory size configurations for the 1500 are 87, 98, and 125 when alfaobd reads them, but I don’t think that alfaobd even writes most of the sizes back correctly. A few examples would be, 130 works when you write it, but 125 is factory. On the HD Rams, 189 is the factory read, but when people add the 50 gal tank, they have to write 194 because writing 189 doesn’t work.

 

[TH22]

Thanks, I'm learning a lot

Any idea what the last field is when trying to change the liters?
Car configuration change: Fuel Capacity (36-290 L): '130.000 LITERS ' -> '158 '
Car configuration change: Fuel Capacity (36-290 L): '194.000 LITERS ' -> '158 '
Car configuration change: Fuel Capacity (36-290 L): '194.000 LITERS ' -> '153 '
Car configuration change: Fuel Capacity (36-290 L): '189.000 LITERS ' -> '153 '
Car configuration change: Fuel Capacity (36-290 L): '189.000 LITERS ' -> '153 '
Car configuration change: Fuel Capacity (36-290 L): '189.000 LITERS ' -> '153 '

 

[Panic]

I live in Australia and the same problem, hope @Jimmy07 suggests a solution

 

[Skeletor66]

Im having the same issue.