Tachometer below peg

Last week the battery in my 2001 Chrysler Town and Country Limited
(~100K miles) was dead. I was out of town so my wife called AAA and
got a jump. It stated fine and has been fine since - with one
exception. The tachometer is stuck below the peg that sits below the
0 RPM mark. When the van is off, the tach needle hangs at about 6
o'clock. When you start it, it shoots clockwise, hits the peg and
stops.

Any idea what happened and how to fix it. I assume the tach issue is
related to the dead batter as I don't think it was like that
beforehand. Although, like I said, I was out of town so maybe
something I am unaware of happened.

Thanks in advance.

 

Hi...

Not a mechanic, just an old long retired electrical guy... so for
what little it may be worth...

Sounds like the meter somehow reversed itself so violently that
it jumped the "peg", and is stuck below it. IF that's the case,
then your only solution is going to be to remove it, disassemble it,
help the pointer gently back to it's correct resting position, and
put everything back together. Or replace the tach

Gives me a flashback back to my early days, when I finally saved
enough allowance to buy an analog meter, and very soon after I got
it tried to measure the resistance of the AC line

Take care.

Ken

 

Do this:

Start with ignition switch off (in "lock" position). While holding the
odometer reset stem in, turn the key to the "unlock" position (that's
the first click of the ignition switch) - continue to hold the odoemter
reset stem in for about 3 seconds. You'll see a self-test of the
instrument cluster begin - part of which includes a dance of the gage
needles to preset positions. At the end of the needle dance, the
tachometer needle will be in its proper position.

In a nutshell, here's what happened (no need to read further if you
don't want to know the "why" of what happened):
The needle somehow got thrown into the wrong position (say - a jolt to
the vehicle with power turned off). The gage needles are driven by
motors that have any one of three unique positions (at 120° intervals)
for a given set of their control signals. Everything is great
until/unless the needle gets into the wrong 120° sector - and then you
see what you are now seeing. Putting the cluster thru the self-test
(needle dance) tries to force the needle clockwise past the peg, but
since it is blocked by the peg, the needle pops back into the correct
sector and forever will read correctly (unless something jolts it into
the wrong sector with ignition power not applied to the cluster).

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

The explanation and the fix is much simpler and easier than all that,
Ken. See my other post.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

THANKS!!!!!!

That did it.