CEL P0136 , P0156 after JB4 installed on N54

blackwind1 · 07-05-2017, 12:44 PM

Hello

I bought used JB4 and installed on Monday.
I get these code sometimes and it keep coming back after delete.

P0136 and P0156

What could be the problem?

Thanks in advance

6ixSpd · 07-05-2017, 03:53 PM

Search in the N54 section.

JStar69 · 06-03-2019, 06:15 PM

Did you figure this one out? I am having the same issue and I was not having it before I disabled the JB4. I can't get it smogged until I do, so any help would be greatly appreciated.

blackwind1 · 06-05-2019, 09:13 AM

I believe the power connection was disconnected from JB4. after re-installing, it was fine. Please check the power cable is securely connected

JStar69 · 06-06-2019, 04:10 PM

The JB4 is functioning even though I have it turned off. I had both downstream O2 sensors replaced Wednesday which isn't cheap and when I accelerated a little bit at take off, the codes came back on. They looked at it again today and said it's the same codes which I already knew. They traced the wiring down a little where then could and then suggested I take it to a dealer as they are used to working on the BMW's complex wiring. They reset the codes for me so my plan is to drive it easy to park and remove the JB4 and see if the problem clears up. If you can give any more insight to your repair, that would be great. Thanks.

blackwind1 · 06-07-2019, 05:02 PM

Yes, It was power connector that one of the wire on JB4. JB4 was working regardless.
Please check the all the wiring

Check page 26~28 of installation manual.
Mine was one of the pin was disconnected.

JStar69 · 06-19-2019, 01:23 PM

Thank you. I ended up removing the JB4, reset the codes with a OBDII reader from Autozone and no more check engine light or O2 sensor codes. When I removed it, the power wire appeared to be connected fine.

For anyone with these two codes, I would recommend unplugging the battery ground from the vehicle for a few minutes and reconnecting to see if you can clear the codes and drive it without them coming back on. If they come back on, it's the JB4 that is causing it so you should check the power wire to see if it's connected properly and if it is connected properly, then you'll have to remove the JB4 from the vehicle all together. This will be the only way to pass smog if your state smog checks plugs in to the OBDII port for testing. Another thing, the smog computer could not communicate with my vehicle with the JB4 installed. This caused an OBDII fail and that flagged me in their system so I can only go to a state smog inspection facility. After removing the JB4 they had no problem communicating with the ECM through the OBDII port. I can finally pass smog. My vehicle is a 2013 BMW 335IS.

07-05-2017, 12:44 PM	#1
blackwind1 Private 0 Rep 59 Posts Drives: 2009 BMW 335xi Join Date: Nov 2015 Location: Toronto iTrader: (0)	CEL P0136 , P0156 after JB4 installed on N54 Hello I bought used JB4 and installed on Monday. I get these code sometimes and it keep coming back after delete. P0136 and P0156 What could be the problem? Thanks in advance
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07-05-2017, 03:53 PM	#2
6ixSpd Save the manuals! 6012 Rep 6,741 Posts Drives: '16 M3, '23 718 Spyder Join Date: Feb 2016 Location: 416 iTrader: (4)	Search in the N54 section. __________________ '16 M3 \| '23 718 Spyder Past: E92 M3, F87 M2, E39 M5, etc
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06-03-2019, 06:15 PM	#3
JStar69 Registered 0 Rep 3 Posts Drives: 2013 BMW 335is Join Date: Jun 2019 Location: SoCal iTrader: (0)	Did you figure this one out? I am having the same issue and I was not having it before I disabled the JB4. I can't get it smogged until I do, so any help would be greatly appreciated.
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06-05-2019, 09:13 AM	#4
blackwind1 Private 0 Rep 59 Posts Drives: 2009 BMW 335xi Join Date: Nov 2015 Location: Toronto iTrader: (0)	I believe the power connection was disconnected from JB4. after re-installing, it was fine. Please check the power cable is securely connected
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06-06-2019, 04:10 PM	#5
JStar69 Registered 0 Rep 3 Posts Drives: 2013 BMW 335is Join Date: Jun 2019 Location: SoCal iTrader: (0)	The JB4 is functioning even though I have it turned off. I had both downstream O2 sensors replaced Wednesday which isn't cheap and when I accelerated a little bit at take off, the codes came back on. They looked at it again today and said it's the same codes which I already knew. They traced the wiring down a little where then could and then suggested I take it to a dealer as they are used to working on the BMW's complex wiring. They reset the codes for me so my plan is to drive it easy to park and remove the JB4 and see if the problem clears up. If you can give any more insight to your repair, that would be great. Thanks.
	Appreciate 0 Quote

06-07-2019, 05:02 PM	#6
blackwind1 Private 0 Rep 59 Posts Drives: 2009 BMW 335xi Join Date: Nov 2015 Location: Toronto iTrader: (0)	Yes, It was power connector that one of the wire on JB4. JB4 was working regardless. Please check the all the wiring Check page 26~28 of installation manual. Mine was one of the pin was disconnected.
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06-19-2019, 01:23 PM	#7
JStar69 Registered 0 Rep 3 Posts Drives: 2013 BMW 335is Join Date: Jun 2019 Location: SoCal iTrader: (0)	Thank you. I ended up removing the JB4, reset the codes with a OBDII reader from Autozone and no more check engine light or O2 sensor codes. When I removed it, the power wire appeared to be connected fine. For anyone with these two codes, I would recommend unplugging the battery ground from the vehicle for a few minutes and reconnecting to see if you can clear the codes and drive it without them coming back on. If they come back on, it's the JB4 that is causing it so you should check the power wire to see if it's connected properly and if it is connected properly, then you'll have to remove the JB4 from the vehicle all together. This will be the only way to pass smog if your state smog checks plugs in to the OBDII port for testing. Another thing, the smog computer could not communicate with my vehicle with the JB4 installed. This caused an OBDII fail and that flagged me in their system so I can only go to a state smog inspection facility. After removing the JB4 they had no problem communicating with the ECM through the OBDII port. I can finally pass smog. My vehicle is a 2013 BMW 335IS.
	Appreciate 0 Quote