just realized after playing in the snow with a friends truck that my ABS dont seem to work as smoothly as his.

i do remember looking and NOT seeing a diode in the ABS diode position...

anyone care to explain what this diode does exactly? 97 f150 lariat.

 

The same as any other diode: it allows current to flow in only 1 direction. The ABS diode is mainly for the dash light, but it's certainly required for the system to work right.

 

You have to look at a drawing to see what the diode does and understand how it works in the circuit.
Being a one way conduction device, it is used to isolate certain switch contact functions that supply ground to light the dash lamp so the light comes on as a warning for certain problems and condition such as the EMG brake on, low brake fluid etc.
Haynes book page 12-30 shows the circuit.

 

oh alright, i was gonna say hey! i cant look in the owners manual, i never got one with this used truck lol.

but i do have a haynes or chiltons book. theyre the same company anymore arent they? i'll have to look at those pages.

any sort of idea of what those diode's would run for?

 

Sorry I don't know what they would cost.
If you found the location, it can be tested with a meter set on resistance and tested for one way conduction or being open or shorted.

 

Haynes & Chilton are certainly not the same company - they're arch rivals. Chilton sells butchered copies of the factory manuals. Haynes reads the factory manuals, strips the truck, puts it back together, & writes their OWN book.

I'd just snag a handful of diodes in the junkyards.



Wait - I already did.

 

Adding on to a very old thread, but I noticed today that my Rear ABS Diode is missing. Took me some time to determine the name of this diode since the manual for my truck, a 1998 F250 light duty 4WD, doesn't document the function of these diodes.

I bought this truck used, so I've never had a diode in this position. I'm wondering if this might be normal for some reason for this truck.