Temp and Fuel Gauges

[boxboy]

I got so much good information when I asked about my headlight issue I thought I should push my luck a bit. My gauges work intermittently, no rhyme or reason that I can see. That says to me that the senders are both good. Is there a common ground for them that I should check? Any other ideas what the problem might be?

[elmerfudpucker]

When dealing with electrical, always check your grounds, that is 90% to blame.

[boxboy]

That is what I am figuring, but where do I find the ground to my instrument cluster? Isn't it just that it is screwed to the dash?

[datzenmike]

I don't think it's a ground problem.

 

power goes to a voltage regulator that provides a steady 8 volts. This prevents gauge fluctuations when the voltage drops at idle and the lights dim. Both gas and temp are run on this 8 volts with the other side going to the two senders. The senders provide a variable resistance to ground to move the gauge needle. If you ground the temp sender wire to the thermostat housing the gauge should go to FULL HOT. Same with the gas gauge.

 

If they are both intermittent the volt regulator wiring may be loose or just old and needs replacing.

[boxboy]

Where is the Voltage regulator located? Sorry. I've only had this thing for a couple of weeks. Who knows what the PO did to the wiring. My other thread tells about how there is no relay for the headlights. My heater which worked fine when I brought it home is now blowing fuses as soon as I pull the switch, my wipers go on, but I have to finesse the switch a bit to get them to stop (and that is usually in the middle of the windshield). Let me know where the regulator is and I will clean the connections.

[mklotz70]

It's a small metal box on the backside of the gauge cluster. It was still available from the dealer a couple of years ago....but I'm sure yours works...you just need to pull it off and on a few times to clean the contacts. I'm pretty sure there's a screw holding it, so don't try to just reach up and and do it.

[banzai510(hainz)]

While driving my 521 pick up I can reach my skinny hand up there on the right side and find the regulater and move it around then it works again.

[mklotz70]

LOL! My stubby arms aren't long enough to do that!

[boxboy]

Okay then. Pencil eraser on the flat contacts and unplug and clean that regulator. One more thing on the mounting list of electrical tasks. My big hands don't fit under there either Mike. I need to disconnect the speedo cable to take out the instrument cluster correct? I can't get tools in there, my hands are too big already!

[MikeRL411]

Okay then. Pencil eraser on the flat contacts and unplug and clean that regulator. One more thing on the mounting list of electrical tasks. My big hands don't fit under there either Mike. I need to disconnect the speedo cable to take out the instrument cluster correct? I can't get tools in there, my hands are too big already!

 

Don't forget, the 2 plug in tabs are 12 Volts in and regulated volts out. The mounting tab with the bolt hole is your only ground and needs to be degunked also. I use an old fashioned "ink eraser" the kind with rubber with fine pumice embedded to clean the tab and lugs, then give a light spray with Radio Shack Color TV Tuner cleaner to prevent reoccurance of corrosion before reinstalling. I have often thought that an 8 volt Zener diode and dropping resistor would be the ultimate fix but as long as my regulator keeps working I have no inspiration to take this any further. Good luck!

[MikeRL411]

Another point. If you really do need to buy a new regulator, the dealer will probably roll his eyes at a 520. The 520 and 410 / 411 use the same unit. When all else fails, get a 1968 [first generation] vintage 510 regulator. You will have to bend the mounting tab to fit the printed circuit board but it will work just fine.

[mklotz70]

you may just try reaching up in there and wiggling it like Hainz mentioned :)

[boxboy]

I think I got it! The tabs were actually pretty clean. There is a small threaded stud on the back of the regulator however that has a copper washer and a snap washer holding it down. That was corroded pretty good. I cleaned that up and moved it around and bingo! Now while I've got the cluster off, I think I will replace the bulbs. Anyone know the part numbers? Mine are so corroded I can't read them. Anyway, thanks for the help.

[banzai510(hainz)]

goin of the top of my hesad the 521 bulbs are LS6501 from Napa

[inline4]

Don't forget, the 2 plug in tabs are 12 Volts in and regulated volts out. The mounting tab with the bolt hole is your only ground and needs to be degunked also. I use an old fashioned "ink eraser" the kind with rubber with fine pumice embedded to clean the tab and lugs, then give a light spray with Radio Shack Color TV Tuner cleaner to prevent reoccurance of corrosion before reinstalling. I have often thought that an 8 volt Zener diode and dropping resistor would be the ultimate fix but as long as my regulator keeps working I have no inspiration to take this any further. Good luck!

wouldn't a zener diode and a resistor be less efficient/consistent as a voltage regulator?

[datzenmike]

This is +40 year old technology that is cheap and it works.

[bilzbobaggins]

check out this thread for using led's on your cluster

 

 

led gauge cluster

[inline4]

This is +40 year old technology that is cheap and it works.

im not saying that it wouldnt work, but it might not be reliable. I'm getting inconsistent temp readings from my factory gauge, its bouncing back and forth sometimes (maybe its grounding out) but when I hooked up the consult port to the ecu, the 510 temp gauge would be in different spots,

 

e.g. at 180 degrees or so, it would be at M, then shut it off and turn it back on, it would show between T and E for about the same.

[Creepy Cruiser]

I've replaced a few gauge regulators in Nissan dashes over the years, and they are super easy. You used to be able to get them from radio shack for about $2, but you can't buy anything there now except cell phones and toy cars, lol.

 

I've never done one in a 510 dash (yet), but this is what I've used in the past, and has worked ever since in all of them. http://www.amazon.co...0/dp/B0002ZPX7I

 

Has anybody tried one of these yet?

 

[inline4]

I've replaced a few gauge regulators in Nissan dashes over the years, and they are super easy. You used to be able to get them from radio shack for about $2, but you can't buy anything there now except cell phones and toy cars, lol.

 

I've never done one in a 510 dash (yet), but this is what I've used in the past, and has worked ever since in all of them. http://www.amazon.co...0/dp/B0002ZPX7I

 

Has anybody tried one of these yet?

 

I'm not quite sure how the gauges work, but when I used one of those for a project that needed a capacitor because voltage wouldnt stick. I'm not sure if it would be the same in this situation. someone school me? or is there a resource for gauge repairs?

[MikeRL411]

wouldn't a zener diode and a resistor be less efficient/consistent as a voltage regulator?

 

No. The Zener diode is a high current avalanch diode and would keep a steady 8 volts. The "dropping" resistor between the 12 volt input and the top of the Zener serves to control the current through the Zener so it won't burn out. The trick is to size the resistor correctly.

 

12 volts in----resistor--|---8 volts out

[Zener]

|

Ground

 

"Sketch" didn't work, the vertical between resistor and 8 volts out goes to "Zener" and the vertical from Zener goes to ground. Confused?

 

No moving parts as in mechanical regulator.