s80 2001 no low beams

[roderick-2012]

Hi, first timer here. My low beams quit working on my 2001 s80.The high beams work.Fuses 1,2,23 all good.power and ground at switch.If I understand the wire diagram,the switch communicates its intention to the CEM which powers the relay.I used a scanner and determined that I could not communicate with the headlight switch.My question is,if I replace the switch,will I need to code/program it to the car to enable its function?

[jimmy57]

The usual problem is the shunt on the 99-04 P2's. There are black strips plugged in the fusebox under the dash on left. That fusebox is part of the CEM.
The power to the low beans goes through the black strip (it is a shunt) so the bulb currents can be measured fir the bulb warning system. The shunts can get loose in the connectors it inserts into.

[roderick-2012]

thanks jimmy57.as i stare at the wire diagram,it appears to be component 20/27?

[jimmy57]

yes, that is it

[roderick-2012]

Thanks jimmy57,the fix was the relay