Fault code 31

[OBR4]

Hi Guys,

I have been having trouble with my 03 navara, the engine light flashes when i turn the car on and i can get rid of it by turning the car on and off twice. This doesnt happen all the time only randomly.
I took in to a mechanic and the plugged in a tester and told be it was a fault code 31.
I was just wondering if anyone would be able to tell me what that code means, I did try ring a nissan service centre but didnt seem to want to help

Cheers for your help

 

[tweak'e]

pays to mention what motor you have.

also you will need to take it to nissan as i'm guessing the mechanics reader doesn't work with these, simply because theres no such thing as "fault code 31"

 

[OBR4]

Sorry it is a 3.0 ltr turbo diesel, ZD30

 

[KraftyPg]

There is a list of generic OBDII trouble codes (which as the name suggests are generic to all OBDII vehicles) and several of them have 31 in them but none have just those two numbers, they usually have several numbers and a letter to distinguish what they relate to.

 

[tweak'e]

trouble is the ZD30 isn't fully OBDII compliant, they don't use generic OBDII codes. hence the need to use nissans reader or a reader that specific to that model.

 

[Old.Tony]

According to the Diagnostic Trouble Code section for the ZD30DDT there is NO code 31. Doesn't mean it isn't there of course, the service manual that Nissan use doesn't have to be complete.

On the KA24, error 31 is for HO2S1 HTR (B1) which in English means "The current amperage in the heated oxygen sensor 1 heater circuit is out of the normal range. (An excessively low voltage signal is sent to ECM through the heated oxygen sensor 1 heater.)".

The cause of that is either a faulty harness or faulty sensor.

 

[tweak'e]

just a thought, could possibly be code 0301 ecu malfunction.

 

[Brock200]

Hi all, i have EXACTLY this same problem. However sometimes it disapears for ages then it comes back and wont go away, even after starting the engine multiple times. However it does seem to co-incide with low fuel, which makes me think it may be due to needing to flush the fuel pump (same engine also). im not sure that it will go away with a full tank of diesel but im going to fill up tomorrow so ill keep you guys posted

 

[tweak'e]

if its only with low fuel, check for air in fuel lines and how hot the fuel tank gets.

the other thing is to check your earths. i actually fitted an extra earth from body to chassis, from middle/rear of cab to gearbox cross member. i think it was the frontiers and some of the patrols which suffered a problem with body not earthing to well to the chassis and causing issues with rear lights and fuel tank senders.

 

[Dave]

^ Gu's had the earthing problem and it usually caused the sub tank to not work.

As Tweak'e said check for air in the lines, the primers in D22's are known to get a bit average. Mine has never had an issue but I have heard of many.

Dave.

 

[tanz]

OBR4,

the guys above are only refering to genuine diagnostic codes when they say there is no code 31. An aftermarket scanner may actually have a different code recognition that's unique to their system (it's way of making you buy the entire system from them).

I'd suggest the mechanic is using a Snap-on tools diagnostic unit. I've done some research and they tell me that the code 31 ECM2 on a ZD30 engined D22 will be related to either a bad earth or a battery voltage supply issue if the battery is a bit weak.

I have the above tool, and have had a customer come to me to have their vehicle checked giving them the above code 31 info and then forgot to follow up until I read this post. If it's you Joseph, then I appologize.

So as mentioned earlier, check and clean all your earth connections.

Cheers.

 

[Brock200]

wouldnt a battery problem flash the battery light rather than the engine light?

 

[tanz]

The battery light is actually an alternator charge light, so unless the alternator has an issue then usually it wouldn't light up.

 

[Brock200]

hmm, well i got a brand spankin new alternator and aparently the previous owner put a new battery in, tho it was in there when the old alternator was screwed. Maybe i should test it with the multimeter? as long as its not doing damage to my engine thats cool... the flashing engine light makes me paranoid, tho the car seems to run fine whilst it flashes

 

[KraftyPg]

First thing I'd be checking if I saw the alternator light on was that the battery was getting volts to it. Wouldn't matter if I'd just replaced the battery and the alternator I'd still check for good voltage at the battery while the engine was running. It could be crappy terminals or anything but like tanz says the light is to warn you the alternator isn't (or may not be) charging the battery not to tell you the battery fell out.

 

[OBR4]

Sorry for the late reply but the problem was a bad earth. It was actually a fault code 31 but i think the mechanic was using a generic tester. He printer out a wiring diagram for me and i just traced all my earths and found one not quiet tight. Problem has not happened since.
Cheers

 

[tweak'e]

thanks for replying. that's handy info for other people later on

 

[Brock200]

unreal, any chance of posting up that pic with the wiring diagram? mine is geting worse and worse, ive upgraded the earthing kit on my S15 so i will have a rough idea on how to do it if you cant post it up.

cheers!

 

[Been a while]

Nothing like reviving an old post,,,,, i was keen to see those earth points also....Cheers

 

[Been a while]

Here is some i have found - L/H Radiator Support panel, L/H Inner Guard mid way, Inlet Manafold, R/H Inner Guard mid way x2. L&R/H Kick panel, Yet to find the ecm one !