Fuel Guages

[rafa]

Hi all.

For some reason my fuel Guages have started showing 3/4 full instead of full. Seems intermittent. Is there a simple fix?

Cheers.

Marty

[NP99]

Start by checking the earthing..

[threedogs]

X 2 earth problem like NP99 suggests

[Cuppa]

Can anyone explain this 'checking the earth' process, preferably specific to the vehicles that Rafa & I have, leaf cab chassis. I have lived with the same problem. If it's just a matter of the main earth to chassis connections, that' not the problem, at least not in my case. I have added extra earth connections. Dropping the fuel tank to get at the connections on top of it seems like a big drama. Is this what is required? It is so frustrating to be able to see all those connections on top of the tank, but just out of reach.
Really though I think it is more likely a dry solder joint in the pcb behind the dash, as someone else has described previously, which is nightmare stuff for me. Not a job I want to attempt myself, but fearful if I take it to Nissan or an auto electrician it could take a long time (& LOTS of cash) to find the cause. Rafa does your sub tank misread too? Mine does, & occasionally the speedo needle, but the problems are intermittent & unpredictable. Much of the time it works ok, but I cannot trust it. Shits me.

Cuppa

[altech]

GU fuel gauge ,I'm so use to mine being out ,I just go by my trip meter of 400 kms per LPG tank of 90 litres .......... regards Alex

[megatexture]

Can anyone explain this 'checking the earth' process, preferably specific to the vehicles that Rafa & I have, leaf cab chassis. I have lived with the same problem. If it's just a matter of the main earth to chassis connections, that' not the problem, at least not in my case. I have added extra earth connections. Dropping the fuel tank to get at the connections on top of it seems like a big drama. Is this what is required? It is so frustrating to be able to see all those connections on top of the tank, but just out of reach.
Really though I think it is more likely a dry solder joint in the pcb behind the dash, as someone else has described previously, which is nightmare stuff for me. Not a job I want to attempt myself, but fearful if I take it to Nissan or an auto electrician it could take a long time (& LOTS of cash) to find the cause. Rafa does your sub tank misread too? Mine does, & occasionally the speedo needle, but the problems are intermittent & unpredictable. Much of the time it works ok, but I cannot trust it. Shits me.

Cuppa
Unfortunately with so many issues like you are having it is more likely behind the cluster like you suspect and I agree that would be a pain in the ass. Can you get an aftermarket fuel guage cheaply and tap into the sender wires where you can reach them on the way to the dash to see if you get the same level as your dash, if it is then you have ruled out the instrument cluster, it must be the sender.

[Cuppa]

Thanks for 'confirming' my nightmare MT! :)
Your suggestion of a separate fuel gauge fits if just one gauge were affected, but despite my best attempts at wishful thinking I don't believe that the cause being sender units in both tanks is likely, particularly as there is a relationship between the misbehavior of both.
Can anyone tell me how many arms & legs (approx $ value would be good) I'd need to sell in a worst case scenario where the instrument cluster needed replacing. Would going to a Nissan dealer or an auto sparky be the best course? I'm guessing Nissan would just want to replace, but how likely is it that an auto sparky would be prepared/able to fault find/repair on the back of the dash cluster.
Living with the issue locally isn't hard, but I must admit I want to be able to trust the instruments for touring & especially any long desert trips.

Sorry if this is a hijack Rafa, but I'm assuming it may also be helpful to you.

[megatexture]

Would it be easier to get an instrument cluster from a wreckers ? Fix any suspisous joints on that one and do a clean swap for minimal down time and labour cost

[Cuppa]

Would it be easier to get an instrument cluster from a wreckers ? Fix any suspisous joints on that one and do a clean swap for minimal down time and labour cost

Another good idea, And another 'yes but' answer......... problem for me would be a)recognising any suspicious joints, & b) fixing them. Have never had anything to do with such things. If I tried I could easily envisage multiple attempts at removing & replacing the dash not knowing if everything was working or not.

Now there's an opportunity for someone familiar with that sort of soldering work. Buy dash clusters from a wreckers, test them to ensure they are working correctly & then sell them to folk like me with a guarantee they are fully operational. I'd buy one if it only meant pulling the dash apart the once. ANY TAKERS? Rodney would you be the man?

Out of interest would the mileage recording of my vehicle be retained, or would it show the mileage of the donor vehicle?

Cuppa

[rafa]

I have been thinking more about when mine started to go wrong, my auto electrician wired in a red arc dual battery system to the third battery in the pod to charge while driving, from the second battery under the Bonnett, he ran a heavy duty positive wire to the third battery, then earthed to the pod. I noticed over the last couple of weeks that the third battery was not charging properly, He has comeback saying may be earthing to the aluminium body was not satisfactory. And has run a heavy duty her back to the chassis. I think this is around the same time that my fuel gauges were mucking up, could it be a coincidence? I am yet to see the error come up with the fuel gauges with the new earth, I will post more later

[megatexture]

Another good idea, And another 'yes but' answer......... problem for me would be a)recognising any suspicious joints, & b) fixing them. Have never had anything to do with such things. If I tried I could easily envisage multiple attempts at removing & replacing the dash not knowing if everything was working or not.

Now there's an opportunity for someone familiar with that sort of soldering work. Buy dash clusters from a wreckers, test them to ensure they are working correctly & then sell them to folk like me with a guarantee they are fully operational. I'd buy one if it only meant pulling the dash apart the once. ANY TAKERS? Rodney would you be the man?

Out of interest would the mileage recording of my vehicle be retained, or would it show the mileage of the donor vehicle?

Cuppa

If your half decent at soldering I'd do all the joints, though it would be a time consuming job to heat, suck away then redo each one. And I was wondering about the mileage also but I think I remember it was stored in the ecu? Happy to be wrong but if it was in the display I'd be wary of buying a 2nd hand trol lol

[megatexture]

I have been thinking more about when mine started to go wrong, my auto electrician wired in a red arc dual battery system to the third battery in the pod to charge while driving, from the second battery under the Bonnett, he ran a heavy duty positive wire to the third battery, then earthed to the pod. I noticed over the last couple of weeks that the third battery was not charging properly, He has comeback saying may be earthing to the aluminium body was not satisfactory. And has run a heavy duty her back to the chassis. I think this is around the same time that my fuel gauges were mucking up, could it be a coincidence? I am yet to see the error come up with the fuel gauges with the new earth, I will post more later

With 3 batteries each earthed individually surely its not an earth issue, well not on the battery side

[rafa]

With 3 batteries each earthed individually surely its not an earth issue, well not on the battery side

I was meaning the earth he ran from the pod battery to the pod he said turned out not up to scratch. It just seems strange that around the time the redarc dual battery system got installed to the the third battery that my previously ok Guages now are not ok. Hmmm

[threedogs]

You may find your earth is broken up into sections along your 4x4,
one earth will be near engine the second may do dash the third the seating area and forth the cargo area,
Something along those lines. you cant expect just one earth off the start battery to do the whole 4x4

[Cuppa]

If your half decent at soldering I'd do all the joints, though it would be a time consuming job to heat, suck away then redo each one. And I was wondering about the mileage also but I think I remember it was stored in the ecu? Happy to be wrong but if it was in the display I'd be wary of buying a 2nd hand trol lol

Further reading suggests mileage changes with change of cluster, but that it is possible to get this changed. Would have to make you wonder how many Patrols are sold with dodgy mileages!
Found this mob (http://www.ebay.com.au/itm/Instrument-Cluster-Speedometer-Odometer-Correction-Repairs-Patrol-Rodeo-Ranger-/331072663660?pt=AU_Car_Parts_Accessories&hash=item4d1577f06c&_uhb=1) on from Adelaide advertising their service on ebay - anyone know of them or have any experience with them?

[macca]

All of these components plug in, a can of contact cleaner and pulling the plugs apart to clean and check they are in fact making a good electrical contact may fix your problem.
A common fault across a few instruments like yours Cuppa suggests the cluster has an earth or plug problem. Even a possibility an earth cable has not been reconnected during some wiring of mods.
Be a pain to remove and resolder the cluster connections if you don't have to.

[Cuppa]

Ok, have had a look at the manual (should’ve done so before) & of course none of the tests are likely to be helpful because of the intermittent nature of the problem, but I can see that pulling plugs apart & giving them a clean would be worthwhile & potentially fix the problems. So I’m looking at giving the connectors for both fuel tank gauges (and maybe the FPC connector?) a spring clean. Trouble is I am unsure how to find them. Do I have to remove the instrument cluster to access the connectors? And are they easy to identify?
What is contact cleaner? I have a pump spray bottle of isopropyl alcohol, would that be ok?

[macca]

The other van has a can of contact cleaner in it, I will have a look when I see my work mate during the week.
CRC CO contact cleaner is one we use.

[Wizard52]

Hi All

Had similar problem when dual battery installed. Fuel gauges would under read and then move back up so really had no accurate idea how much fuel left.
The under tray 2nd battery was only earthed to tray mounting point, so when Battery World up here in the Bay recently installed solar panel and regulator, they ran another earth wire from 2nd battery back to same point on the block where main battery was earthed.
Problem solved.

[Cuppa]

Hi All

Had similar problem when dual battery installed. Fuel gauges would under read and then move back up so really had no accurate idea how much fuel left.
The under tray 2nd battery was only earthed to tray mounting point, so when Battery World up here in the Bay recently installed solar panel and regulator, they ran another earth wire from 2nd battery back to same point on the block where main battery was earthed.
Problem solved.

Any chance you might draw a wiring diagram of your full charging setup & post it or PM it to me? This intrigues me. My aux batteries are earthed similarly, to the aluminium pod, & from the pod to the chassis via a tray mounting point too, but I can't for the life of me understand how this could have any effect on the instrument cluster. My aux batteries are charged via a dc to dc charger & by solar. Essentially the two battery systems are separate. I can't see how using the chassis as a common earth would have any effect, let alone how providing a further direct negative connection between the two batteries could help.
I don't doubt that your problem was fixed, but I would like to understand exactly how, if that extra earth is responsible.
Any chance that whilst the work was being done that any other connections may have been disturbed?
And what size wire did they run back to the block? I'm tempted to run the extra earth like you have, but with an inline switch so I can run as is, & when the fuel gauge problem occurs, flick the switch & see if it immediately comes good.

I might wait to see if this solution works for Rafa.
I can't remember if the gauge problem on my vehicle preceded the installation of my aux batteries or not.

Cuppa

[macca]

Cuppa when this happens have you tried using a jumper lead from the aux negative to the cranker's negative?
Even disconnecting the negatives from the aux battery pack might show a difference in the cluster instruments.

[Cuppa]

Cuppa when this happens have you tried using a jumper lead from the aux negative to the cranker's negative?
Even disconnecting the negatives from the aux battery pack might show a difference in the cluster instruments.

No I haven't tried it Macca, but that is essentially what I meant by use of a switch. Disconnecting the aux negative might be a bit impractical as I have several earths to the pod, & one main earth from pod to chassis (which is switched & only switched on to parallel the aux batts with the crank). Disconnecting the earths to pod could be done, but not conveniently. It is possible that those earths have continuity to the chassis via the pod mounting bolts, even though the pod is now mounted on rubber pads. When the problem occurs I'll firstly try paralleling the aux batts with the crank. If that has no effect I,ll try running another earth wire direct from aux to the neg terminal of the crank ....... But if that were to work I still would have no idea why.

Cuppa

[Yendor]

Any chance you might draw a wiring diagram of your full charging setup & post it or PM it to me? This intrigues me. My aux batteries are earthed similarly, to the aluminium pod, & from the pod to the chassis via a tray mounting point too, but I can't for the life of me understand how this could have any effect on the instrument cluster. My aux batteries are charged via a dc to dc charger & by solar. Essentially the two battery systems are separate. I can't see how using the chassis as a common earth would have any effect, let alone how providing a further direct negative connection between the two batteries could help.
I don't doubt that your problem was fixed, but I would like to understand exactly how, if that extra earth is responsible.
Any chance that whilst the work was being done that any other connections may have been disturbed?
And what size wire did they run back to the block? I'm tempted to run the extra earth like you have, but with an inline switch so I can run as is, & when the fuel gauge problem occurs, flick the switch & see if it immediately comes good.

I might wait to see if this solution works for Rafa.
I can't remember if the gauge problem on my vehicle preceded the installation of my aux batteries or not.

Cuppa

Hi Cuppa,

The chassis on the Patrols is not earthed. If you have a look at the main battery the negative cable connects to the body (just under the battery) and to the engine.

The fuel sender units mounted in the fuel tanks have a small gauge earth wire running to the senders, the design of the the sender unit when bolted in the tank and the tank bolted to the chassis rail supplies a small earth to the chassis. This earth wire is small and can only just handle the circuit for the fuel gauges. In the early Patrols it couldn't even handle this, there were all sorts of problems with the sub tank transfer and the fix was to run an earth lead to the chassis.

When accessories or other batteries are added to the vehicle and use the original earth circuit this can very easily overload it and cause all sorts of problem. The body of the vehicle should not be used as an earth for high current drawing accessories, the chassis can be used but you will also need to run an earth lead from you battery/batteries to the chassis.

Your solar panel shouldn't cause any problems. The DC-DC is not a generator it still relies on the alternator. Where is the DC-DC charger mounted?

Cheers Rodney

[Cuppa]

Hi Rodney,

BCDC1240 is mounted in the pod.

I have sent you a PM.

Cuppa

[Wizard52]

Hi Cuppa

I'll draw and scan basic plan and check size of wire tonight and post it tomorrow.

At the time there were all sorts of theories from various people and experts around here and down in Brisvagas but in the end, the earth fixed the problem.

cheers

[Cuppa]

Hi Wiz, no need now mate, thanks. Yendor has explained the problem, & his suggested solution having looked at a wiring diagram of my set up is to try adding a further earth cable between the neg terminal of the crank battery & the chassis. I am optimistic that this will fix the problem. I had not considered a) that the chassis itself is not earthed directly on Patrols ( had tested continuity, but this doesn't tell capacity, only connection & b) that it is possible to overload an earth. If this solution doesn't work for me, then the problem will most likely lay within the instrument cluster, but as I say, I'm optimistic that this will fix the issue.

Others have previously said 'earthing problem' but I hadn't really understood just what that might mean until Yendor,s post.
Anyone else with the problem should try the simple adding an extra earth direct to chassis. I think your additional earth would have achieved the same outcome, but easier to run the earth from crank battery to chassis, rather than, in my case, another wire from inside the pod to under the bonnet.

Cuppa

[macca]

Good luck Cuppa hope it works

[rafa]

When my auto elec upgraded the earth to to third battery in the pod the gauges went back to being ok.

:)

[threedogs]

Might have mentioned it on another thread but Tojos earth out sections of the 4x4. EG;;;; headlight, engine bay, dash ,front cabin, rear cabin ,cargo and rear bar.
With Nissan I don't think one earth could do the whole 4x4, I'll be running extra earths over the next few weeks

[Yendor]

This was posted on the other Patrol forum. It was taken from a Nissan Learning Manual.

Those guys that are also having trouble with their keyless entry not working correctly may also want to try adding this earth.

Cheers Rodney

[Cuppa]

Some Feedback.
It’s taken a while because I don’t yet clock up a lot of kilometres in my Patrol.

I fitted a heavy duty extra battery to chassis earth cable as Yendor suggested & have now run a full tank of fuel through the motor. I am most pleased to report that like Rafa’s experience, the additional earth has fixed the problem, & my fuel gauge now reads ‘normally’ It’s great to once again have a gauge I can rely on.
Thanks Rodney.

Cuppa

[Wizard52]

Had same issue until dual battery under the tray was earthed back to the block where main battery was earthed. Previously it was only earthed to steel frame under aluminium tray. No problem since.

[Yendor]

Some Feedback.
It’s taken a while because I don’t yet clock up a lot of kilometres in my Patrol.

I fitted a heavy duty extra battery to chassis earth cable as Yendor suggested & have now run a full tank of fuel through the motor. I am most pleased to report that like Rafa’s experience, the additional earth has fixed the problem, & my fuel gauge now reads ‘normally’ It’s great to once again have a gauge I can rely on.
Thanks Rodney.

Cuppa

Thanks for the update Cuppa, Glad to hear it has sorted your problem.

Now all we need to do is get Darren to fit his and see if it fixes his remote problem. :smile:

[Robo]

This was posted on the other Patrol forum. It was taken from a Nissan Learning Manual.

Those guys that are also having trouble with their keyless entry not working correctly may also want to try adding this earth.

Cheers Rodney

Rodney, can I get my hands on a copy, Nissan Learning Manual?.
looked through manuals here, didn't see it listed.
tar Robo

[GU CAMPER]

I have been having the same problems

Yesterday I put an extra earth from the crank battery to the chassis as Yendor had suggested and Cuppa has done. The fuel gauges worked perfectly today so far. Fingers crossed it has solved my problem to

[Yendor]

Rodney, can I get my hands on a copy, Nissan Learning Manual?.
looked through manuals here, didn't see it listed.
tar Robo

Sorry for the late reply mate.

Todd has informed me it is listed on this forum (I couldn't find it either)

Here's the link http://www.nissanpatrol.com.au/Y61-CRD-TM1.pdf