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General Rpm gauge

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General Rpm gauge

Assuming it works the same as other modern(ish) rpm gauges, on start-up it does a quick sweep to check operation, or after a battery disconnect it calibrates itself.

So chances are, assuming you haven't had the speedo cluster to bits, it either needs to recalibrate or the stepper motor's on it's way out. So first stage I'd suggest is disconnecting the battery for a while, and see if it relearns correctly when the ignition's turned back on.
 
Mine allways goes from 0rpm resting position to around the 6 position during starting and I'm sure a family members did exactly the same I'll try and have a look next time I'm withe there car
 
chris3234 said:
Ignore that it's doing it again
Click to expand...

Looks to me like it's starting from the wrong location; if it fixed itself when you disconnected the battery but then lost the setting again it could be the stepper motor's on the way out, or the motor's shaft has got corroded somehow. Might be worth pulling the cluster out, removing the cover, taking the needle off, giving the shaft a gentle clean, plug it all back in and put the shaft on position '0' once it's done it's calibration to see if that fixes it...

If it doesn't work, are you any good at soldering? :)

Edit: another thing it might be - if the rpm needle normally has a little pin just past 0 to find it's rest position and the pin's fallen out, that'd cause it too; if that is the case you'll hear a little rattle when you take the cluster out, or might see a small hole where the pin should be if you peer closely at the rev counter.

Edit2: Woah! o_O


Presumably wrong for your car, but that might give some clue as to which pins to point a multimeter at, if you get that far inside the speedo cluster
 
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mj2k said:
Looks to me like it's starting from the wrong location; if it fixed itself when you disconnected the battery but then lost the setting again it could be the stepper motor's on the way out, or the motor's shaft has got corroded somehow. Might be worth pulling the cluster out, removing the cover, taking the needle off, giving the shaft a gentle clean, plug it all back in and put the shaft on position '0' once it's done it's calibration to see if that fixes it...

If it doesn't work, are you any good at soldering? :)

Edit: another thing it might be - if the rpm needle normally has a little pin just past 0 to find it's rest position and the pin's fallen out, that'd cause it too; if that is the case you'll hear a little rattle when you take the cluster out, or might see a small hole where the pin should be if you peer closely at the rev counter.

Edit2: Woah! o_O


Presumably wrong for your car, but that might give some clue as to which pins to point a multimeter at, if you get that far inside the speedo cluster
Click to expand...

The pictures are for a classic Tipo so will be nothing like a modern one

As for it not starting in the right position I'm fairly sure that where it allways start from even when it dosnt do that noise
 
chris3234 said:
The pictures are for a classic Tipo so will be nothing like a modern one

As for it not starting in the right position I'm fairly sure that where it allways start from even when it dosnt do that noise
Click to expand...
I thought as much for the doc I found, but interesting to see how much depth people have gone into for the gauge in the past; I thought it was pretty impressive :) You'll probably find similar test points on a modern pcb to above though if you need to pick up the signals passed through though.

As for the starting position, maybe that is normal (others would know better than me) but it does seem quite unusual to start from below 0 rpm and complete the sweep half way up; if it's not able to find it's zeroing point (some rev counters do use a little pin as a zero point) it'd be more likely to 'panic' so to speak when in operation. Worth a quick check just in case before condemning the instrument cluster (assuming you don't decide to put up with the issue) since popping a little pin back in is a quick cheap option, if that's all it is.
 
mj2k said:
I thought as much for the doc I found, but interesting to see how much depth people have gone into for the gauge in the past; I thought it was pretty impressive :) You'll probably find similar test points on a modern pcb to above though if you need to pick up the signals passed through though.

As for the starting position, maybe that is normal (others would know better than me) but it does seem quite unusual to start from below 0 rpm and complete the sweep half way up; if it's not able to find it's zeroing point (some rev counters do use a little pin as a zero point) it'd be more likely to 'panic' so to speak when in operation. Worth a quick check just in case before condemning the instrument cluster (assuming you don't decide to put up with the issue) since popping a little pin back in is a quick cheap option, if that's all it is.
Click to expand...
All the other cluster I've seen online rest at the 6 position when not running so I doubt there's any sort of pin missit prehaps somebody else with a Tipo can post what there cluster does
 
RichardH13 said:
Almost certainly, its the battery.
When the voltage starts to drop weird things happen
Click to expand...
Seems odd the battery gauge on the dash still showed around 2/3 but obviously isn't very accurate and it still spun around Fairly quickly but then again it's a Fairly low compression engine on the 1.4 16v


The battery would also explain why it seemed to do it more often on a cold morning
 
Almost certain that'll be the battery - my Tipo did it at the start of the year. The battery had gone flat once over Christmas & been charged by the dealer, but then the juddering gauges started. The car continued to start fine for quite a while but with the dials doing the juddering, then it gave up again. Dealer ran a battery test & it failed so Fiat replaced it under warranty and no repeat of the problem since. If its just the 95bhp 1.4 then a new battery shouldn't be too costly as there's no start-stop on them if I remember correctly?
 
JTD_Liam said:
Almost certain that'll be the battery - my Tipo did it at the start of the year. The battery had gone flat once over Christmas & been charged by the dealer, but then the juddering gauges started. The car continued to start fine for quite a while but with the dials doing the juddering, then it gave up again. Dealer ran a battery test & it failed so Fiat replaced it under warranty and no repeat of the problem since. If its just the 95bhp 1.4 then a new battery shouldn't be too costly as there's no start-stop on them if I remember correctly?
Click to expand...
One ordered £73 decided 59 pay little more for a efb type even though it doesn't have start stop only another £14 should hopefully make it last a little longer good brand as well yussa
 
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