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Discussion Starter #1
Hi guys! My Stang is 2005 V6 stick shift but the problem I ran into may also apply to any vehicle, I guess. My temperature gauge was acting weird so I replaced it's stepper motor. Connected the cluster back, did some initial calibrations, all was good. Even after I turned the ignition off. But! After each engine start the temp (new motor) and speedometer gauge needles drop a few degrees left, in other words, I have to calibrate the needles every time the engine is started! I could think of replacing all 4 motors, but temp motor is new and behaving good until the engine is re-started (or ignition key turned all the way right without actually starting the engine by not pressing the clutch and stop pedals), and old motors of tachometer and gas are almost ok after re-starts. I shot a video which describes this mess better:


So what things to do next? Thanks!!
 

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It's hard to guess just looking at a video, but it gives the impression that the new stepper in the temp gauge is either faulty, damaged, or possibly an old style stepper that got mixed in with a new batch. If the speedometer is starting to mess up then its stepper is probably going bad too. When I did my cluster I just went ahead and replaced all the steppers at once, as the old style steppers will will always fail eventually.
 

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I believe you are supposed to set the base line of the gauges with the key in the off position, then try them.

If they are not correct, then reset them again whilst key is in the off position.


all stepper motors cycle gradually (you can hear it) to zero, or all the way to their left (counter clockwise) with the key off.

There are also YouTube videos explaining some of this.

Usually setting any gauge to just below zero, or just a hair to left of lowest line on gauge...with key in off position gets them close to where they should be.

Fuel gauge may be the only exception...that needs to be set, maybe with key on and tank full to full mark on gauge....then retest..key off, key on.
The low fuel light is totally separate from the fuel gauge. When it shows low fuel, I believe (not sure) there is about 1 1/2 gallons of fuel remaining in tank. So that in itself is a good gauge of how much fuel you have in tank, regardless of what gauge may say. The fuel tank actually holds more than the stated 16 gallons.

Believe me regardless of what the fuel gauge says, even if it's wrong, when the low fuel light comes on, it means you have 1 1/2 or fewer gallons remaining. It has a totally different sender or sensor in the tank, from the one which tells the fuel gauge what's happening.

All gauges should drop to all the way to left...or just below lowest mark on any gauge when key is off.
 

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My understanding, if correct from videos I've seen is this:

Once a new stepper motor is installed.....with the needle off that gauge...you turn the car ignition to on once...then turn the ignition to off once...This sets the new motor to zero...Then set the needle on that gauge to zero, or slightly below lowest line of that gauge with the key off.

As for the fuel...I think it's like this: when the gauge shows 1/4 tank we assume the tank has four gallons remaining, but it may have as many as 5 1/2 gallons remaining.

When the fuel gauge shows 1/2 tank we assume it has 8 gallons, but actually may have 9 1/2 gallons...and so on.

I would assume the above if I don't have enough money to fill the tank, yet need to set the fuel gauge needle. I'd drive till the low fuel light comes on, then immediately drive to a gas station, add say 4 gallons of fuel. Then I'd know to set the fuel needle to 1/4 tank, telling me the car has four gallons of fuel remaining, BUT it actually has 5 1/2 gallons remaining.
 

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Discussion Starter #6
with the needle off that gauge...you turn the car ignition to on once...then turn the ignition to off once...
Thank you soooo much bro!! Did as you said (but prior to that replaced all 4 motors just in case, not just the temp motor) -- they all work as supposed to! Wooo weeee!!

That's why I did wrong the first time, I guess:
https://www.youtube.com/watch?v=HUljDi8hOwc

Again, thank you!!
 

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I wrestled with this when I replaced all stepper. Do this...plug in your cluster without the needles on. Then turn your key forward and step just before you start the car. Now all steppers ar zeroed. Then push needles on. All should be good now.

Dan
 
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