T-guage and Fuel gauge regulator?

[fisch]

Howdy Ratsun experts. Can you use a volt meter to test a regulator? (I barely know how to use a volt meter. And I know a regulator regulates the current, but I have no idea how to test it!)

 

Allrighty according to my manuals, if the t-gauge and the fuel gauge on the 521 are both not working, the first suspect is the regulator (I am assuming the one on the back of the gauge pod?)

 

I've already went through and cleaned every connection I could find. Including every spot on the printed circuit and the harness connectors. Everything Ohm reads, guages included. Even made sure the ground at the gas tank was working for the fuel sender.

 

I pulled the regulator, It had a loose blade on the circuit board for sure. But I have that fixed. Reassembled and still nada.

 

Now all that is left is the regulator. I tried to get an ohm reading from poll to poll, and the needle won't budge. Should it move?

 

I ran the part #. Nissan no longer has these, but Nissanparts.cc does. But before I order it, am I missing other options? I see regulators for Datsuns on ebay, but they all have different connectors. Radio shack options?

 

I was about to hit the confirm order on Nissanparts.cc, they are anly $15 so no big deal at all. But thought I'd check in with the pound first to see if it should ohm read, and if not it is truly dead.

 

Rock the Dat.

[banzai510(hainz)]

did you ohm out the trace to where it went to the connector to the Can to make sure a complete trace???????.

Sometimes they can have a hairline crack in the circut board under the insulation.

 

 

best would be to swap in another dash if one is avail.

Somehow I found the power feed and the ground,

I had a varible DC power supply and put like 0 thru 6volts on there and both the gas gauge and fuel gauge would move the same amount. PS I DID NOT put 12volts on there Mine worked.

 

I found out the fuel gauge was grounding out at the top of tank. Solder broke of on top of fuel sender. JB weld!!!!!!!!

[fisch]

did you ohm out the trace to where it went to the connector to the Can to make sure a complete trace???????.

Sometimes they can have a hairline crack in the circut board under the insulation.

 

 

best would be to swap in another dash if one is avail.

Somehow I found the power feed and the ground,

I had a varible DC power supply and put like 0 thru 6volts on there and both the gas gauge and fuel gauge would move the same amount. PS I DID NOT put 12volts on there Mine worked.

 

I found out the fuel gauge was grounding out at the top of tank. Solder broke of on top of fuel sender. JB weld!!!!!!!!

 

Hainz with the regulator removed I individually traced the connection from where the regulator plugs in on the board, to the stopping point on actual gauges and the needle on the volt meter would move. So I think power would travel those paths. I just couldn't get a reading on the regulator itself.

 

Should I get a ohm reading from blade to blade on the regulator itself? Cause I get nothing.

 

Heh I just missed a guage pod on ebay last week for like $16. Prolly should have jumped on it just to have a spare.

[banzai510(hainz)]

Should I get a ohm reading from blade to blade on the regulator itself? Cause I get nothing.

 

 

I cant remember!!!!!!!! I assume you would read a high resistance if you have a digital mutimeter

[fisch]

Should I get a ohm reading from blade to blade on the regulator itself? Cause I get nothing.

 

 

I cant remember!!!!!!!! I assume you would read a high resistance if you have a digital mutimeter

 

Heh I have the cheapest, smallest stocking stuffer of a volt meter ever created.

 

You know, since no one is selling a replacement gauge cluster at the moment on ebay. And if they were it'd be alot more than the $15 Nissanparts.cc is asking for a new regulator, I will just spend the cash at Nissanparts.cc and see if it works. After all both the Haynes and the Datsun manual say if there is a problem with both gauges, it is most likely the regulator. The one on there is kinda rusty looking on the casing anyway, and with how dirty every connection has been on this rig, who knows what is going on inside that regulator case.

 

I will report back if it fixes the situation!

[Datsun4u]

Fisch, I might have a extra gauge cluster for you. pm me if you need it.

[fisch]

Fisch, I might have a extra gauge cluster for you. pm me if you need it.

 

Cool! I just might at that. PM sent.

[ggzilla]

I have Nissan factory manual. For the instrument panel regulator it doesn't say how to test it but says this:

The voltage regulator is combined with the thermometer... replace it together with the thermometer

Since 1200 and 620 use the same gauges, i suspect this applies to both. My book if the 1200 factory book.

[yello620]

I have Nissan factory manual. For the instrument panel regulator it doesn't say how to test it but says this:Since 1200 and 620 use the same gauges, i suspect this applies to both. My book if the 1200 factory book.

 

But odes it apply to a 521?

 

Have you ground out the sensor wire to see if the guage reads then? Unplug sensor wire from temp sensor at motor and hold it to ground with key on. this just helps check the sending unit if the needle moves now.

 

This worked on my 620 temp guage, assume that the 521 L motor is the same.

 

Jason

[fisch]

Thaks for the insight GG and Yello!

 

I was looking at the factory manual for the 521 and it didn't mention having to replace the thermo too, but I will double check.

 

I will also perform the test you suggested Yello and see if it budges. The t-sender looked brand new when I installed it a few months ago, but was a used on someone kindly gave to me, so you never know!

 

I've ordered the regulator, so when it arrives I will slap it on and see if it does anything.

[banzai510(hainz)]

Mine is acting up also

 

comes and goes right now. I assume connection since both move the same amount!!!!!!!!!!

[racerx]

The problem with ohm readings is that you can still get some reading but it may not be enough to make a good connection... typically you want to find what the ohm values are...

 

Anyways maybe this will help from dime quarterly...assuming that the cluster set-up is similar or the same as a 510

 

 

http://www.dimequarterly.tierranet.com/

[racerx]

Oops..look under electrical and there's a section for temp. and fuel gauge repair...

[dat521gatherer]

first thing first, take your test light check the fuse box with the ignition switch on and make sure you have power on both sides of all of your fuses.

 

next stick your test light on the temp sending wire at the temp sending unit with the wire disconnected from the unit. if the gauge doesn't move there is a problem with the cluster (pod).

 

usually the printed circuit board gets melted and the copper printing is then junk unless you soilder a wire strand where the break is. seen burnt circuit boards on at least 75 percent of 521's

 

i've never seen a burnt gauge let alone 2 or a bad volt gauge reg. still possible

 

disconnect your cluster plug and take your test light and stick it the hole with the yellow/green wire. with the key on your test light should light up saying you have gauge power at the plug. or if your oil light or ignition light works then you have power going to the cluster.

 

if you can crawl under the dash or pull the cluster out far enough to leave the harness plugged in you can take your test light and with the ignition on there should be power on both sides of the gauge volt reg.

 

does your oil,ignition light work? dash lights work? if no to all your not getting power from that yellow/green wire. the cluster (pod) needs to be grounded (screwed down) for the dash lights and turn signals but not for the oil light or ignition light or gauges.

 

if your oil light or ignition light works then you have power to your gauge volt reg.

 

if this doesn't help or when in doubt just start swapping shit out.:D

[dat521gatherer]

thank jesus your not trying to figure this out on a 620. harder to take apart and 50 times more wires. it's no wonder the fuse boxes melt along with the rest of those harnesses. fucking double backing wires everywhere. the 521 harness is way more straight forward.

 

just figuring out how to take out a 620 cluster with the hidden bolt and figuring out how to get the light switch out can end up breaking both.:eek: i like to play with wires but the 620's just piss me off.:mad: that and the damn harness changed every year towards the end.

 

521's rule!! i smell another poll coming on.

[dat521gatherer]

here is a tip for everybody. take your test light and stick it each hole on your cluster harness plug and tweek(pry) the round connector closed just a hair on each one. i've never seen a corroded connection on these but they do become loose from removing them.

[fisch]

Well guess what, the manual was indeed right and it was the 8 volt regulator on the back of the gauge pod! I have full gas and temp readings now.

 

And I am happy to report with 10 min of running and driving around the yard, the temp stayed just below the little mark they have on the white line and only went up to the half way point when I shut it down.

 

Interesting about these regulators. I took my old one apart (before I got the new one) to see if I could fix it somehow. Wow is it simple under that metal case. Mine was so dirty and oxidized. I got it cleaned up and put it back in. But when I turned on the key on all that happened was the fuel meter went up for a split second and went back down. Then nothing. They must be very sensitive cause I cleaned the hell out of it.

 

Anyway to recap. If your fuel and temp gauge are not working, or ir they are squirly, and you've traced the connections and they look good. Try to replace the regulator. It is like $15 at Nissanparts.cc. Which is cheaper than a whole used pod that might have the same issue! (Especially on the east coast!)

 

Feeling good fellahs, I think my 521 is ready to drive! And I no longer have question marks about what the temp is doing!

[Pacific coast Datsun]

Good to know Fisch. My 620 is having similar issues. Glad yours is fixed.

[dat521gatherer]

good going i think i'll buy a new one myself.

 

not knowing how much fuel or what your engine temp is sucks.

 

recently i was driving my hornet and i looked down and my needle was missing from my fuel gauge. i figured it fell off. when i shut the car off i saw the needle appear from behind the full line and fall to empty.

 

now i notice when the body flexes like going in and out of parking lots the needle starts acting up. i hope i dont find a can of worms on this one.