toyo 80 series elect speedo

[bradley]

sorry if this has been asked b4 or i messed it up

my 80 series toyo model 11/93 speedo stopped working i think its the sender unit but not sure it has 3 wires a red a brown and yellow the red reads 7.8 to 8 volts

the yellow 12.4 volts the brown seems to be earth. i hooked it up to a drill to spin it and the volts remain the same. toyo are asking $400 for a new sender unit.

i want to be sure if this is the problem.

there does not seem to be any pulses that i can read with a multi meter

any help of info would be great

thanks

[Dave]

sorry if this has been asked b4 or i messed it up

my 80 series toyo model 11/93 speedo stopped working i think its the sender unit but not sure it has 3 wires  a red a brown and yellow the red reads 7.8 to 8 volts

the yellow 12.4 volts the brown seems to be earth. i hooked it up to a drill to spin it and the volts remain the same. toyo are asking $400 for a new sender unit.

i want to be sure if this is the problem.

there does not seem to be any pulses that i can read with a multi meter

any help of info would be great

thanks

←

The pulse train is likely to be too fast for a multimeter to read (unless it has a freq setting). I suspect the duty cycle would remain constant across the speed range, thus the voltage AVERAGE (what most meters will indicate on DC mode) would also be constant.

The voltages sound roughly correct.

If you turn the speedo sender with a drilll (on high speed setting) there should be some indication on the speedometer (cant tell you what as I have not actually checked on mine - its too wet outside :-(

Is the signal wire intact (the wire with the 8V reading) back up to the loom on the gearbox (the 8V is generated in the sesnsor)?

Dave