5ktq speedometer error

[Kurt Deschler]

Ameer,
I looked at the circuit and guage internals. The circuit is pretty simple. 
It converts a pulse from the sender to an analog voltage. There is 
no adjustment on the guage but this could be added easily on the analog 
side with a potentiometer. I suspect that there is a bad capacitor or D/A 
convertor that is making the guage pulse on mine. I have an extra board 
from the junkyard to swap parts from now. I will send an update when I get 
a chance to fix my guage.
 	-Kurt

  It looks like a pretty simple 
pulse counter with a D/A converter and analog


> Message: 1
> Date: Sun, 29 Apr 2007 12:17:58 -0400 (EDT)
> From: Ameer Antar <antar at comcast.net>
> Subject: Re: 5ktq speedometer error
> To: Quattro List <quattro at audifans.com>
> Message-ID: <31940233.121177863478126.JavaMail.SYSTEM at jeves>
> Content-Type: text/plain; charset="us-ascii"
>
> I know this is a really old topic, but I just noticed that even though the
> speedo is 4-5mph over true speed, the trip computer does register pretty close
> to the correct speed. I cleared the average speed on the computer, and it
> showed 76mph while the speedo showed about 80. So it looks like the offset is
> in the speedo only. I wonder how that affects the odometer mileage since it's
> part of the speedo. Does anyone know of a VDO gauge specialist? I wonder if it
> can be re-calibrated...
>
> -Ameer
>
> -------------------- Original Message --------------------
>
>> Message: 5
>> Date: Thu, 25 Jan 2007 17:04:51 -0500 (EST)
>> From: Kurt Deschler [desch at alum.wpi.edu]
>> Subject: 5ktq speedometer error
>> To: quattro at audifans.com
>> Message-ID: [Pine.LNX.4.63.0701251701130.24874 at cs.wpi.edu]
>> Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
>>
>>
>> The speedo on my 5ktq is around 6mph on the high side. In addition, it
>> pulses at low RPMs. My suspicion is a bad capacitor somewhere, but I
>> really know how these speedos work. Anyone seen this before or have a fix?
>>
>>     -Kurt
>>     87 5kcstq
>>     89 200tq
>>     00 s4
>>     95 s6
>>
>>