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99streetranger
Well-Known Member
- Joined
- Aug 2, 2023
- Messages
- 83
- City
- Virginia
- Vehicle Year
- 1999
- Engine
- 3.0 V6
- Total Drop
- 3 Front, 5 Back
I am trying recalibrate the GEM in my 1999 Ranger to calculate the correct speed for my tire size.
Firstly, Forscan is unable to read the DTCs in the GEM. Is this a fuse that is popped or a bad ground somewhere causing this? I can read DTCs from the PCM just fine. I am using this adapter: https://www.amazon.com/dp/B094Z7PBLS?tag=959media-20 which is listed as one of the recommended adapters on the Forscan website.
Secondly, I am having trouble writing data to the GEM only with the As-Built method. The list view type of configuration works just fine, although I cannot fine-tune.
I was following this thread: https://www.therangerstation.com/forums/index.php?threads/programmer-tuner-for-2-5l.172360/ This thread applies to my model generation and by all accounts should work since the GEM controls speed calibration on these trucks. I am not able to modify the value in the AS-BUILT format like in the thread, even though my rotations per mile (810) is 032A in hex and should work. It reports a format error and the write fails. I am however able to change my tire size via the plain view configuration, however the smallest tire size I can pick is only at 800 rotations per mile which still causes my speedometer to be off. It is better, but it isn't perfect.
Firstly, Forscan is unable to read the DTCs in the GEM. Is this a fuse that is popped or a bad ground somewhere causing this? I can read DTCs from the PCM just fine. I am using this adapter: https://www.amazon.com/dp/B094Z7PBLS?tag=959media-20 which is listed as one of the recommended adapters on the Forscan website.
Secondly, I am having trouble writing data to the GEM only with the As-Built method. The list view type of configuration works just fine, although I cannot fine-tune.
I was following this thread: https://www.therangerstation.com/forums/index.php?threads/programmer-tuner-for-2-5l.172360/ This thread applies to my model generation and by all accounts should work since the GEM controls speed calibration on these trucks. I am not able to modify the value in the AS-BUILT format like in the thread, even though my rotations per mile (810) is 032A in hex and should work. It reports a format error and the write fails. I am however able to change my tire size via the plain view configuration, however the smallest tire size I can pick is only at 800 rotations per mile which still causes my speedometer to be off. It is better, but it isn't perfect.
