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Discussion Starter #1 (Edited)
Hi all. I was using my JB4 software to connect to my car today. I was double checking that my boost limit and Fuel Open Loop settings were correct and after saving, I went to restart the car. I got several error lights including a yellow "brake" light, yellow CEL, and a yellow "4x4" light. The car cranks and after a bit will start, but it's a few seconds. When I turn the car off, I get a yellow car on lift warning in the center.

Any idea what's wrong and how to fix it?
 

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Discussion Starter #3
I'm the car's newest owner, and I've only had it for about 4 months. Unsure if previous owner had the HPFP replaced.

Update: I took out the JB4 and everything's fine. Starts instantly, no error codes, nothing wrong. Any ideas why the JB4 would cause those issues?
 

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I'm the car's newest owner, and I've only had it for about 4 months. Unsure if previous owner had the HPFP replaced.

Update: I took out the JB4 and everything's fine. Starts instantly, no error codes, nothing wrong. Any ideas why the JB4 would cause those issues?
Any chance you know which generation JB4 you have? i would shut the car down reset it and reinstall jb4 after the ecu turns off and see if that helps.
 

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Discussion Starter #5
It's a JB4 G5 ISO. I tried disconnecting the battery first for 10 min before getting around to removing the JB4 which unfortunately did not affect anything.
 

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Discussion Starter #7 (Edited)
JB4 was installed and running perfectly for 3 weeks before today. Checked the upped boost limit and FOL in the JB software to ensure it saved from last week and this happened.
 

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Discussion Starter #9
Update 7/3: Looks like the JB4 power wire started coming lose and ended up breaking off when I took the JB4 out to look at it. I believe it was getting intermittent power and causing my issues. I ordered a JB3 to JB4 power wire from BMS, hooked it up, and the car is back to it's wonderful old self.
 
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