Tachometer is moving up and down like crazy
- Thread starter 290 GDT
- Start date
This sounds like two issues. The tachometer runs off a signal from the alternator and the "milemeter" or odometer from a sensor /encoder at the back of the transfer case. When the plug to this sensor gets wet it makes your SPEEDO do crazy things and your odo stops working.
I dont know where to start tracing the alternator signal except to check that the instrument cluster ground wires are tight. You will find them all together somewhere near the steering column.
I dont know where to start tracing the alternator signal except to check that the instrument cluster ground wires are tight. You will find them all together somewhere near the steering column.
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I think the sensor for the tacho sits on the bellhousing where it counts the teeth on a "sprocket" by the ring gear. Could also possibly be direct on the ring gear.
I do think however you are talking about the speedometer? In that case the odo is not counting because a small gear has lost a tooth or more. There is a thread on this.
I do think however you are talking about the speedometer? In that case the odo is not counting because a small gear has lost a tooth or more. There is a thread on this.
I apologise that iI confuse you with the "tachometer".... I mean speedometer in fact!
You have already gave me the path to start with.
I will check for the cable/socket that sends the signal from either tranfer case or bellhousing!
Plus I will check for the thread that Alan mentioned.
Million thanks
You have already gave me the path to start with.
I will check for the cable/socket that sends the signal from either tranfer case or bellhousing!
Plus I will check for the thread that Alan mentioned.
Million thanks
Also have a look here: https://www.mb4x4.co.za/index.php?resources/290-gdt-wiring-diagrams.1/
I found that my instrument cluster is the A4615400847.
I took it out and behind there are only 2 electric cables that are connected with.
On the other hand I found, as you can see in the attachment that there is a speed signal sender unit (No 29) that I am trying to locate, unsuccessfully so far.....
The serial continued....
I took it out and behind there are only 2 electric cables that are connected with.
On the other hand I found, as you can see in the attachment that there is a speed signal sender unit (No 29) that I am trying to locate, unsuccessfully so far.....
The serial continued....
