Re: looking for1948 overdrive wiring schematic

Posted by HH56 On 2015/5/13 20:38:07

The R9 was used on early 48s & if you have that unit the R9 OD schematic is on the next to last page of the 22nd series wiring diagram. R11s were introduced toward the mid to second half of 22nd series production so if your car is later you may have that unit and that schematic is mentioned in the previous post.

To identify your unit without crawling under, look at the relay on the firewall. R9 has a squarish black box with 6 terminals, R11 has a smaller rectangle shape with 4 terminals and a fuse on the side.