1996 E300 (diesel)

I am attempting to trouble shoot some AC/Heat problems and I have an error code of b1462 Wide Open Throttle (WOT) position signal (diesel engines). Does anyone know what this means and what I need to do to fix it?

The blower is erratic so I am going to be replacing the regulator with the S-Class regulator according to the DIY instructions. The heat and AC temp seem to work fine, but selecting Defrost vs floor or center console has no effect on airflow.

I have a bunch of issues that I need to knock off that I think are unrelated (resonator flap valves on the intake are causing a check engine lite (the dealer told me this a while back and said it didn't effect anything so it could wait) - although I read the codes yesterday with the tool from Harbor Freight and it says there are no codes (CEL still on though). Also the SRS light comes on and stays on.

I just want to get the defrost fixed first so I don't end up crashing when the windshield fogs. I removed the glove box attempting to find the distribution block to see if it could be leaking but I haven't found it yet. There is something wrapped in vinyl with 2 black zip ties that may be it. If that is it, should I attempt to take it out and test it for leaks?

-Pete