HELP! JB4 keeps disengaging and going to Map 0

PFMUSTANG · Nov 17, 2024

Hey guys, I have a JB4 piggyback tuner on my 2024 2.3 7MT. Been battling an issue the entire time I’ve had it. When the obd2 cable is plugged in and I’m doing a WOT pull, the tuner automatically dissengages and puts the car back in Map 0. If I disconnect the cable and run it only off of Bluetooth, it seems to keep it activated. Something is wrong with the device when the cable is plugged in, which is frustrating because all of the gauges are not functioning when unplugged and also the map/mode changing feature is disabled as well. Anyone had any similar issues? Terry sent me a new chip and new obd2 cable and the same thing happened on the very first pull after the install. Not sure what to do.

burgerking · Nov 17, 2024

I was under the impression that the JB4 always has to be plugged into the OBD port to function. You might be going over the boost safety limit if you haven't raised it from the default setting. On the laptop version it's under the user adjustment tab. Not sure on the phone app, I don't have the bluetooth option. I've also been kicked down to map zero for AFR lean when I was running a little too much E85 in the tank.

PFMUSTANG · Nov 17, 2024

burgerking said:
I was under the impression that the JB4 always has to be plugged into the OBD port to function. You might be going over the boost safety limit if you haven't raised it from the default setting. On the laptop version it's under the user adjustment tab. Not sure on the phone app, I don't have the bluetooth option. I've also been kicked down to map zero for AFR lean when I was running a little too much E85 in the tank.

I thought so too but it doesn’t need to be plugged in. The boost was raised but that’s not the issue because it doesn’t disengage when it’s unplugged, only plugged in.

burgerking · Nov 17, 2024

I think the OBD2 has to be plugged in. It says
Plug the OBDII wire in to the JB4 green/brown pair connector. If you’re able to connect to the JB4 with the app but only
see boost and map data, but no other data, then likely the OBDII cable is misaligned, loose, or damaged.
There's a box under user adjustments that says Last Safety. I've seen a 1 for boost over safety and 2 for AFR lean. Haven't seen any of the other ones.

PFMUSTANG · Nov 17, 2024

burgerking said:
I think the OBD2 has to be plugged in. It says
Plug the OBDII wire in to the JB4 green/brown pair connector. If you’re able to connect to the JB4 with the app but only
see boost and map data, but no other data, then likely the OBDII cable is misaligned, loose, or damaged.
There's a box under user adjustments that says Last Safety. I've seen a 1 for boost over safety and 2 for AFR lean. Haven't seen any of the other ones.

I replaced the cable already. I am able to see all the gauges when it’s plugged in, but when I unplug it you don’t see the gauges. The tune works fine when unplugged but doesn’t work when plugged in, so I’m missing features. Swapped between 2 different cables so has nothing to do with misalignment.

burgerking · Nov 17, 2024

It's not reading the gauges because it's not plugged into the OBD2 port. When it's not plugged in you're running the stock ECU tune. The MAP and TMAP pass through the JB4 unmodified. All the piggyback tuners for the bronco have to be plugged in to the OBD2 port in order to work.

PFMUSTANG · Nov 17, 2024

burgerking said:
It's not reading the gauges because it's not plugged into the OBD2 port. When it's not plugged in you're running the stock ECU tune. The MAP and TMAP pass through the JB4 unmodified. All the piggyback tuners for the bronco have to be plugged in to the OBD2 port in order to work.

So your telling me that Terry from Burger Tuning is wrong.

PFMUSTANG · Nov 17, 2024

burgerking said:
It's not reading the gauges because it's not plugged into the OBD2 port. When it's not plugged in you're running the stock ECU tune. The MAP and TMAP pass through the JB4 unmodified. All the piggyback tuners for the bronco have to be plugged in to the OBD2 port in order to work.