Flashing brake light.

I have an 89 Astro. I have a with my brake light on my dash. The light is flashing what looks like a code. I don't have ABS on the van. The code is 1 long flash and 9 short flashes. This code repeats over and over. I have tried looking this up and can't find what it means. I hope someone can tell me what it means.
Thank you.

You say you don't have ABS - but I'll bet you have rear wheel ABS- you are flashing a code "9" which means there is a circuit fault with the rear wheel ABS-

Measure your voltage between pins "A" & "H" on ALDL (diagnostic plug) connector at base of dash- if voltage is "0" then most common reason for flash is a blown DRAC/cluster fuse-

If voltage is 8-15 volts then check for open circuit in rear wheel speed sensors- which I believe on your van is at the drive shaft -

Has any brake work been done? bleeding the lines? how about rear wheels-

I have had this happen where the master cylinder was replaced- and the code appeared- and the mechanic forgot to reset the code- with his scan tool...

I don't have rear ABS ether. I don't have any sensors on the rear wheals at or at the drive shaft.

What about the sensor on the rear of the transmission or transfer case?