Today, glow plug light doesn't come on, car starts OK (was in garage overnight) then light comes on for about 30 seconds. This repeats thru the day. OK it's a recognized problem and this forum has info about it.

But, now the climate control blows cold air unless temp dial is set to full high, or defroster is pressed.

Is this a pure coincidence or is there something that could possibly produce these two conditions with one component failure.

All advice gratefully accepted. Car has about 157K and otherwise performs well.

Has wiring harness been replaced?

__________________
-- Chris

'95 E300, 216k miles, Silver Surfer
'05 E320 CDI, 138k miles
'07 S550 4matic, 69k miles

Gone but not forgotten:

'76 300D, 350k miles?, SOLD in 1995
'75 240D, 300k miles, SOLD in 1991

I believe wiring is original - thanks for the input.