TF signal W124 260E 1988 help
 

I would like to know what king of signal is on TF socket on a W124 260E 1988, euro, on the fuel pump remay?

It is said that if theTF signal (RPM) is missing for 1 sec then it cuts the fuel delivery.

Is it a continuous voltage, a pulsed signal, or something else?

Thanks for help

It is a square wave signal processed by the ignition controller from the AC inducted signal coming from the crank sensor at the same frequency.

Many thanks Steve and my apologies for coming so late, but could not reply before.

Is it a square 12 V or lower?

I have drawings showing that it comes from the injection control unit and not the ignition unit, what is right?