JB4 Install Help
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2019 C43
JB4 Install Help
just purchased a pre owned jb4 for my 2019 c43 installed it and car starts up really ruff and sounds really bad and also does not turn when i try to start it i currently dont have a data log cable just purchased one but any help?
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C43
Man!! Talk about a run on sentence lol, I would check and make sure you have the JB4 plugs plug into the right tap point. The fact that you say it runs rough I would start there, also check what map it’s on.
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2019 C43
haha ya waiting for the data cable to come in to see what map its on. the seller just told me that he mistakenly told me he ran the jb4 on his 2019 but msg him yesterday and said he meant 2020 could that be my issue ?
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2019 C43
i was sold without any data cable or bluetooth but as soon as i get my data cable praying this week ill keep you updated hopefully you can help any confusion i have
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From: in a van down by the river...
2020 C43 sedan(hers), 2021 Porsche 992 TurboS(his)
wtf did you expect?
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The 2020 model runs a different firmware than a 2019 would.
https://www.n54tech.com/forums/showthread.php?t=28003
Firmware:
Note firmware is for JB4 systems only (with OBDII plug installed) and not for Stage1 systems. Loading JB4 firmware to Stage1 systems will render them inoperable at best requiring you to panic email us for Stage1 firmware, and at worst requiring you to remove the tuner and send the Stage1 control board in to be reflashed.
SENT firmware is for 2019+ C300 systems where firmware version ends in //7 indicating a SENT based system.
C_2020 firmware is for 2020+ C400/C450/C43 models which has a special CANbus system relative to previous models.
JB4_MB_C_6:
1) Changed VALET mode to map8, map4 is now between map3 and map5 boost levels.
2) Increased sensor sampling rate for smoother performance.
JB4_MB_C_4:
1) Added support for optional BCM (Boost Control Module)
JB4_MB_C_3:
1) Fixed firmware bug preventing fuel pressure (green) connection from working properly. First generation harnesses (that have an unused purple connection) still must relocate the green wire in pin #20 to pin #4 using a DSUB removal tool. Note this connection remains optional and is only suggested for those running heavy E85 mixtures and high boost levels. Reference photo here: https://www.n54tech.com/forums/attac...1&d=1539975810
2) Adjusted boost scaling for colder climates, should targeting during colder weather. Note, the ECU is LOAD based so the factory boost target will be lower during colder weather than warmer weather. The difference between boost and ECU_PSI should roughly equal the requested boost over stock target.
3) Added fuel trim monitoring in bank2, to go along with the existing AFR monitoring in bank2. Useful for troubleshooting fueling problems.
https://www.n54tech.com/forums/showthread.php?t=28003
Firmware:
Note firmware is for JB4 systems only (with OBDII plug installed) and not for Stage1 systems. Loading JB4 firmware to Stage1 systems will render them inoperable at best requiring you to panic email us for Stage1 firmware, and at worst requiring you to remove the tuner and send the Stage1 control board in to be reflashed.
SENT firmware is for 2019+ C300 systems where firmware version ends in //7 indicating a SENT based system.
C_2020 firmware is for 2020+ C400/C450/C43 models which has a special CANbus system relative to previous models.
JB4_MB_C_6:
1) Changed VALET mode to map8, map4 is now between map3 and map5 boost levels.
2) Increased sensor sampling rate for smoother performance.
JB4_MB_C_4:
1) Added support for optional BCM (Boost Control Module)
JB4_MB_C_3:
1) Fixed firmware bug preventing fuel pressure (green) connection from working properly. First generation harnesses (that have an unused purple connection) still must relocate the green wire in pin #20 to pin #4 using a DSUB removal tool. Note this connection remains optional and is only suggested for those running heavy E85 mixtures and high boost levels. Reference photo here: https://www.n54tech.com/forums/attac...1&d=1539975810
2) Adjusted boost scaling for colder climates, should targeting during colder weather. Note, the ECU is LOAD based so the factory boost target will be lower during colder weather than warmer weather. The difference between boost and ECU_PSI should roughly equal the requested boost over stock target.
3) Added fuel trim monitoring in bank2, to go along with the existing AFR monitoring in bank2. Useful for troubleshooting fueling problems.
Thread Starter
Junior Member
Joined: Dec 2021
Posts: 22
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2019 C43
The 2020 model runs a different firmware than a 2019 would.
https://www.n54tech.com/forums/showthread.php?t=28003
Firmware:
Note firmware is for JB4 systems only (with OBDII plug installed) and not for Stage1 systems. Loading JB4 firmware to Stage1 systems will render them inoperable at best requiring you to panic email us for Stage1 firmware, and at worst requiring you to remove the tuner and send the Stage1 control board in to be reflashed.
SENT firmware is for 2019+ C300 systems where firmware version ends in //7 indicating a SENT based system.
C_2020 firmware is for 2020+ C400/C450/C43 models which has a special CANbus system relative to previous models.
JB4_MB_C_6:
1) Changed VALET mode to map8, map4 is now between map3 and map5 boost levels.
2) Increased sensor sampling rate for smoother performance.
JB4_MB_C_4:
1) Added support for optional BCM (Boost Control Module)
JB4_MB_C_3:
1) Fixed firmware bug preventing fuel pressure (green) connection from working properly. First generation harnesses (that have an unused purple connection) still must relocate the green wire in pin #20 to pin #4 using a DSUB removal tool. Note this connection remains optional and is only suggested for those running heavy E85 mixtures and high boost levels. Reference photo here: https://www.n54tech.com/forums/attac...1&d=1539975810
2) Adjusted boost scaling for colder climates, should targeting during colder weather. Note, the ECU is LOAD based so the factory boost target will be lower during colder weather than warmer weather. The difference between boost and ECU_PSI should roughly equal the requested boost over stock target.
3) Added fuel trim monitoring in bank2, to go along with the existing AFR monitoring in bank2. Useful for troubleshooting fueling problems.
https://www.n54tech.com/forums/showthread.php?t=28003
Firmware:
Note firmware is for JB4 systems only (with OBDII plug installed) and not for Stage1 systems. Loading JB4 firmware to Stage1 systems will render them inoperable at best requiring you to panic email us for Stage1 firmware, and at worst requiring you to remove the tuner and send the Stage1 control board in to be reflashed.
SENT firmware is for 2019+ C300 systems where firmware version ends in //7 indicating a SENT based system.
C_2020 firmware is for 2020+ C400/C450/C43 models which has a special CANbus system relative to previous models.
JB4_MB_C_6:
1) Changed VALET mode to map8, map4 is now between map3 and map5 boost levels.
2) Increased sensor sampling rate for smoother performance.
JB4_MB_C_4:
1) Added support for optional BCM (Boost Control Module)
JB4_MB_C_3:
1) Fixed firmware bug preventing fuel pressure (green) connection from working properly. First generation harnesses (that have an unused purple connection) still must relocate the green wire in pin #20 to pin #4 using a DSUB removal tool. Note this connection remains optional and is only suggested for those running heavy E85 mixtures and high boost levels. Reference photo here: https://www.n54tech.com/forums/attac...1&d=1539975810
2) Adjusted boost scaling for colder climates, should targeting during colder weather. Note, the ECU is LOAD based so the factory boost target will be lower during colder weather than warmer weather. The difference between boost and ECU_PSI should roughly equal the requested boost over stock target.
3) Added fuel trim monitoring in bank2, to go along with the existing AFR monitoring in bank2. Useful for troubleshooting fueling problems.
Thread Starter
Junior Member
Joined: Dec 2021
Posts: 22
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2019 C43
Banned
Joined: Nov 2021
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AMG CLS63
