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BMS VW GTI JB4 info thread

George Smooth

Drag Race Newbie
Location
South Africa
Started my car up today and I was changing from Map 2 to 6 which caused a slight knocking sound. As soon as I threw the car into reverse the sound went away. Stayed in my driveway and scanned for codes in the JB4 app and it showed a 3ad2 code, low fuel rail pressure. Well I won't be changing Maps anymore while the car is on, but has this happened to anybody? This has happened before once, but I didn't put the two together. It also threw the same code.

Could be glitch with the app or with the Bluetooth data transfer.

if you got that code stored though drop you fuel open loop by 10.
 

zoominms3

Ready to race!
Location
Buffalo NY
got a 509E code and a 49f5 code just updated to 6b firmware.. please advise?

:update: I cleared the codes a few times, then disconnected and reconnected and they appear to have cleared now.
 
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George Smooth

Drag Race Newbie
Location
South Africa
got a 509E code and a 49f5 code just updated to 6b firmware.. please advise?

:update: I cleared the codes a few times, then disconnected and reconnected and they appear to have cleared now.

They both rear O2 sensor related.
49F5 is downpipe related and is a variance of primary O2 in turbo and rear one on cold start.
Second one is heater circuit fault. In most cases the O2 sensor either has a ground issue on the DP, might be damaged from over tightening or on its way out. I have also seen faults like this when you using the O2 sensor fuse to power something else and the voltage drop is too much.
 

AlienSP

Ready to race!
Location
Austin, TX
Accelerated yesterday, about 70% throttle, got an EPC light and went into limp with no boost (3gal E85, rest of tank 93. Run 3 fills of pure 93 before E85 mix again). Outside=101F, IAT=140-160F. Map6 with IE intercooler. JB4 codes were 3AD200, 000000. Cleared codes, switched to Map0.
This morning, 84F, got EPC and code 3B123B. Cleared and filled up with 93 octane. This afternoon, 104F, got EPC and 3B1200. All EPCs were triggered by mid throttle and eliminated with restart of car. Could you please offer some direction with the hex code translation? Many thanks in advance!
 

Diggs24

Autocross Champion
Location
de plains! de plains!
Car(s)
2015 GTI
Accelerated yesterday, about 70% throttle, got an EPC light and went into limp with no boost (3gal E85, rest of tank 93. Run 3 fills of pure 93 before E85 mix again). Outside=101F, IAT=140-160F. Map6 with IE intercooler. JB4 codes were 3AD200, 000000. Cleared codes, switched to Map0.
This morning, 84F, got EPC and code 3B123B. Cleared and filled up with 93 octane. This afternoon, 104F, got EPC and 3B1200. All EPCs were triggered by mid throttle and eliminated with restart of car. Could you please offer some direction with the hex code translation? Many thanks in advance!

The first is low fuel pressure. Recheck your settings. Make sure fuel bias is all 100 and FOL is 60.
 

elamothe15

Ready to race!
Ok helpppppp....

I went to go turn my JB1 back on tonight. I was on stock map 0 while I was breaking in the new clutch. Anyways I went to change to map 1 and the JB1 / Software freaked out on me. The map would not go to 0, 1, or 6 and went to crazy numbers like 155, etc. For example, I would select map 1 and the window would display a crazy number. Also all of the settings in the window (map 6 boost settings, meth settings, and everything) all updated randomly.

Since the map 6 updated randomly out of a range of 25 it doesn’t seem like the map changed from 0 but all of the other settings are all still messed up. My only sigh of relief is that when I quit the JB4 app and reload and connect it says map 0 still.

Any ideas on what happened or what I can do to fix this? I posted this in the JB1 thread, but this seems to get more views now and the operation is the same.
 

Nappy216

Ready to race!
Location
Lowell MA
State inspection

Here in MA they have to plug into the OBD port for inspection.

Will switch to map0 and unplug the JB4's obd connector.

Does the car have to re-learn when switching maps?
Need to do a few WOT when I switch from Map6 to Map0 (and back again)??
 

miked617

Go Kart Newbie
Location
Boston, MA
Car(s)
21 VW GTI
Here in MA they have to plug into the OBD port for inspection.

Will switch to map0 and unplug the JB4's obd connector.

Does the car have to re-learn when switching maps?
Need to do a few WOT when I switch from Map6 to Map0 (and back again)??

No re-learning needed. You can switch on the fly and the new map is immediately active.
 

dood.

Drag Racing Champion
Location
Seattle
Car(s)
2017 GTI S DSG
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