2010 G37x code P0306

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Danbam
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Car: Infiniti G37x AWD

2010 G37x code P0306

Postby Danbam » Tue Aug 23, 2022 7:51 pm

So I have code P0306 I troubleshoot it, everything came down to I don't get a spark on coil #6, I have tried that coil and other coils they work but in that wire it doesn't, I thought it was the wire so I clipped it because the original one had a chip or insulation missing, I've checked voltage on pigtail connector on that particular cylinder/coil #6 and others I get a reading of BV but coil #6 won't create a spark, chime on this for me please!
Last edited by Rogue One on Wed Aug 24, 2022 4:17 am, edited 1 time in total.
Reason: Revise Title


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VStar650CL
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Car: 2013 Nissan Altima 2.5 SL
2004 Nissan Altima 2.5 S

Re: 2010 G37x code P0306

Postby VStar650CL » Tue Aug 23, 2022 8:24 pm

It has to have both power and ground, make sure a test lamp between the 12V and ground wires lights up brightly. If it doesn't, but there's battery voltage at the 12V pin, then you know the ground wire is broken. It's also possible you have a pin-fit problem at the connector, either check it with an 0.025" safety pin or just try a replacement pigtail. You could also have a broken signal wire, back-probe it with the engine running and make sure you have the same voltage on that wire as on the coil from a good cylinder. If they're different then the signal wire from the ECM has an issue.

Danbam
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Joined: Tue Feb 18, 2020 9:28 pm
Car: Infiniti G37x AWD

Re: 2010 G37x code P0306

Postby Danbam » Tue Aug 23, 2022 8:35 pm

First of all thank you for your help. VStar650CL I did put a new pigtail at this point I'm thinking It could be related to the ignition condenser but I don't want to keep tearing apart to be disappointed also I'm leaning towards ecm because to me it makes no sense all other work except that one signal is not being sent by computer.

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VStar650CL
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Re: 2010 G37x code P0306

Postby VStar650CL » Tue Aug 23, 2022 9:00 pm

The condenser is connected between the 12V supply and ground, so it would affect all 6, not just #6. It's also rare for just one signal driver in the ECM to fail, usually the whole chip fails. So check your ground and compare signal voltages, because chances are you have a wiring problem. If ground is good but you find a difference in the ECM signal to the bad coil, then ohm the wire back to the ECM. If continuity checks good and pin-fit is good at both ends, then you can suspect the ECM. You can find the ECM pin reference on EC-521 and the wiring diagram on EC-532:
https://www.nicoclub.com/service-manual ... 0%2FEC.pdf

Danbam
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Car: Infiniti G37x AWD

Re: 2010 G37x code P0306

Postby Danbam » Wed Aug 24, 2022 1:38 pm

I understand your logic. By any chance do you happen to know if I run new ground wires on top of existing ground would help the situation or should I do my own grounds once I trace all the ground wires in wiring harness?

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VStar650CL
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Re: 2010 G37x code P0306

Postby VStar650CL » Wed Aug 24, 2022 2:07 pm

The easiest way to spot bad grounds is voltage drop, and with coils it's very simple to do. With the engine running, back-probe the coil ground pin and measure from it to the battery negative terminal. Ideally you'd see 0V, but in the real world ground wires have a slight resistance, so you should see something under 50 millivolts (0.05V). If it's much higher or it reads battery voltage, the ground is bad. Here's a primer on how to test grounds:
keep-your-engine-on-the-ground-not-just ... 28130.html

Danbam
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Car: Infiniti G37x AWD

Re: 2010 G37x code P0306

Postby Danbam » Sun Aug 28, 2022 6:40 pm

So today I had a mechanic come over and he confirmed what I already knew pigtail connector 6 has normal voltage and coil works but I get no spark, through him doing his tests we found out as he back probe the light blue wire with probe plugged to positive side of terminal also utilizing a test light touching that light blue wire my coil sparked but every time he would disconnect the test light it wouldn't spark, he never said anything about the computer being bad but he also never said whether the computer is good he was baffled that the coil sparks with light test what do you think about this situation? I believe my computer is messed up can you please chime on this and also if you know what's the actual computer I need to get and how do I make sure I'm getting the right one, if I'm not mistaking this car has 2 computer one close to the battery and one under the glove box.

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VStar650CL
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Re: 2010 G37x code P0306

Postby VStar650CL » Sun Aug 28, 2022 7:41 pm

The ECM is behind the glove box, the one in the engine box is the VVEL Controller (valve timing). It sounds like you do have a bad ECM, but the only thing bad is the pullup resistor for the drive transistor on #6. The test light was acting as a source of pullup voltage to the circuit. That's a weird one, I've never seen it before, but the transistor must still be healthy if the coil started firing when pulled up. You can probably save the ECM by wiring a 1K 1/2-watt resistor between the 12V and signal wires at the coil.

Danbam
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Re: 2010 G37x code P0306

Postby Danbam » Sun Aug 28, 2022 8:00 pm

Yeah I was thinking about doing that in the mean time meanwhile I gather the computer since idk much of what to look for because idk what the difference would be with them but I'll do some research since that's what my car has made me do for quite sometime now, hey man I thank you for help your very knowledgeable and a great help with all this info and the best is FREE shows character.

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VStar650CL
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Re: 2010 G37x code P0306

Postby VStar650CL » Sun Aug 28, 2022 8:31 pm

Pay the knowledge forward. That's all I'm doing.
:dblthumb:

Danbam
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Re: 2010 G37x code P0306

Postby Danbam » Sun Aug 28, 2022 8:45 pm

🤸 keep up, I sure do appreciate you. If you got any input on what I should look for when buying a computer that would be sweet and what the process would be to install it do I need a reflash depending on ecm I get or if I get a compatible to my car maybe no reflash needed. Let me know anything you might know

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VStar650CL
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Re: 2010 G37x code P0306

Postby VStar650CL » Mon Aug 29, 2022 5:10 am

On a '10 the I-keys need to be registered, so it definitely won't be plug-and-play. You can see the list of what needs to be done on EC-17 here:
https://www.nicoclub.com/service-manual ... 0%2FEC.pdf

Honestly, if it was my car I'd try a pullup. Shame to replace a very expensive engine computer over a burned out $0.001 resistor, which is essentially what this seems like. One of these will probably fix you right up:
https://www.ebay.com/itm/371659830820

Danbam
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Car: Infiniti G37x AWD

Re: 2010 G37x code P0306

Postby Danbam » Mon Aug 29, 2022 11:03 am

Ok, well I am going the resistor way but I would like to have it work the way it was supposed to as well but for now I'll do a resistor btw I have a few resistors that are 9.14 would those be good enough or you recommend 1k instead. Thanks in advance.

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VStar650CL
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2004 Nissan Altima 2.5 S

Re: 2010 G37x code P0306

Postby VStar650CL » Mon Aug 29, 2022 11:38 am

I assume you mean 9.14K. You could try them, it might work. I don't know how much bias current the gate in the coil actually needs. Power rating won't be an issue with anything above about 2.4K, so it's worth a shot.

Danbam
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Joined: Tue Feb 18, 2020 9:28 pm
Car: Infiniti G37x AWD

Re: 2010 G37x code P0306

Postby Danbam » Mon Aug 29, 2022 11:56 am

My bad and yes I meant 9.14k. and ok Ill keep you posted in a few days or sooner depending on the outcome. Also should I run it from the battery or should I just run it from the connector itself for example solder the resistor to the power source of the coil connector and bridge it with the signal wire or from battery to signal wire. I'm trying to do it clean if I don't have to run a wire then better.

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VStar650CL
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Re: 2010 G37x code P0306

Postby VStar650CL » Mon Aug 29, 2022 12:19 pm

Just run it next door to the 12V wire on the connector. Once it works, you can wrap it together and nobody but you will even know it's there. Solder-shrinks will work fine, if you don't have any you should get some. They're God's gift to proper wire repair.
https://www.ebay.com/itm/144143567342

Solder Shrinks.jpg
Solder Shrinks.jpg (13.21 KiB) Viewed 126 times

Danbam
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Car: Infiniti G37x AWD

Re: 2010 G37x code P0306

Postby Danbam » Mon Aug 29, 2022 7:48 pm

Ok, I see what your saying and exactly how I wanted to do it you can't see no cable but for some reason the scanner still saying cylinder 6 misfire but definitely don't feel as rough since I get off work pretty late and go in early not enough time in a day to actually mess with it, but I'm going to take the spark plug out and see if perhaps something might be wrong with it or probably I'll get the 1k 1/2 watt resistor instead.


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