hi

I'm having some trouble getting my vss signal correct to ecm and speedo.

Using a 4l80E magnetic vss 40pulses/rev and a 1227749 ECM with code59.
I wired it to magnetic vss inputs on ecm and speedo/cruise to the correct outputs and checked the magnetic vss flag. But what do I set the VSS ppm to and speedo pulse divider to.

/N.

 

About ump-teen-zillion.

Best bet is to get a DRAC and wire it in. It will feed an 'optical' signal to the ECM, plus the proper signals to the speedometer and the cruise control (if present).

The best part of a DRAC is that they are strap programmable. So can set it for the tire diameter and rear gear ratio that is installed. And reset it if either are changed.

RBob.

 

ok, where can I find a DRAC? need it ASAP

any part number?

Also just tried to unhook ECM and the the TCI software showed mph correct I guesss the vss signal is to weak to be used to both TCI and ECM....

/N.

 

Astro's are an EXCELLENT source for the DRAC. If present, located in the center of the dash, right next to the vent. (up near the windshield, not the floor)

Full size Blazers/Suburbans (old body style stuff) '90-91 also used them, but unsure where exactly they mounted it.

I found Astro's as a good source because there were simply so many of them. Unsure of exact vintage, but I assume it had to be a range of years around '90.

 

A part number would help alot then I an call around here in sweden to locate one, Astros and blazers are not that usual over here

 

Sorry, didn't notice your location.

If you get a part number, can you get it locally, or will it still have to come from the States?

I don't have the part number, sorry, but I think I've still got a spare sitting around...

 

The problem with a part number is that each different strapping (programming) is a different part number. There are way too many to list.

If they know what a DRAC is, ask for it by that name. It doesn't matter which one you start with. They are all strap programmable.

Digital Ratio Adapter Controller... Small plastic box about 4 x 4 x 1" (10 cm x 10 cm x 2.4 cm).

RBob.

 

Lets see if that pic works

 

Got one VSSB but they didnt send any contactharness with it but I had some small pins that fit so I "re-"soldered the VSSB to fit my gear ratio/tire size and tested it, and it WORKS!

Speedo and ECM shows speed, had to set *.bin to 4000ppm but thats all, shall hook up Cruise control next thing and then solder all connections and make the installation "permanent".

 

Super, for the outputs: 2K PPM are pins 1 and 11, the 4K PPM pins are 4, 14, & 15.

RBob.