VDO Tach dip switch positions

[j_lowder]

I am wiring a VDO Tach (333 538) in my '79 FJ40 rebuild with a 2F engine. The signal originates for the Tach Output from my DUI Ignition distributor/coil unit. My Tach has 8 dip switches. All the instructions that I can find show only 3 with the positions for a 6 cylinder: #1 On, #2 Off, and #3 On. Setting only these three switches does not produce an accurate rpm reading.

Help would be much appreciated.

 

[bsevans]

I am wiring a VDO Tach (333 538) in my '79 FJ40 rebuild with a 2F engine. The signal originates for the Tach Output from my DUI Ignition distributor/coil unit. My Tach has 8 dip switches. All the instructions that I can find show only 3 with the positions for a 6 cylinder: #1 On, #2 Off, and #3 On. Setting only these three switches does not produce an accurate rpm reading.

Help would be much appreciated.

I ran into the same problem and used the digital rpm display on my timing light to match the rpms on the VDO gauge. Only one of the dip switches needs to be moved, but I cannot remember which one. I remember that it only took a couple of minutes to get the switches in the right position. I called VDO about this issue and they said they would look into it.

 

[j_lowder]

bsevans

Thanks for the reply. Do you remember if all of the other dip switches were in the off position? On my unit some are in the on and some in the off positions.

 

[bsevans]

bsevans

Thanks for the reply. Do you remember if all of the other dip switches were in the off position? On my unit some are in the on and some in the off positions.

I'll see when I can pull the instrument panel so I can take a mirror and see what the dip switch placement is.