hi guys,

my 940 turbo (91) has speakers in the dash (powered by radio head) and speakers in the rear doors (powered by an amp under the stearing wheel - might be pasanger side if u r in the usa..) It has wiring for the front door speakers,but no speakers...so I thought i would add some.


having put in some panasonic speakers (i know not much quality..but exactly the right size :-)) i now find i have NO sound from them...i have checked following


1. i have signal voltage on all 4 signal feed pins on the din connector from the radio to the amp, plus 12 volts on the amp turn on line.

2. i have 12volts/ 0volts on both feed and earth lines to the amp.

3. i have continuity on the lines from the socket that plugs into the amp to all 4 speakers (can measure resistance with meter, and 1.5 volt battery 'bump' test works fine.

I have come to the conclusion it has to be an issue with the amp..so the questions are...

1. Does the amp actually support 4 speakers...i mean are there different amps some of which do, some of which dont? I have seen posts before that suggest it should..but does anyone know? if not can i simply swap in an after market amp that does (accepting having to do wiring changes...) or do the volvo head units use funny signal voltages?

2. Does the amp have a switch somewhere that need to be thrown?

3. Does the head unit in some way 'switch' the amp...

4..am i a complete idiot and missing something really obvious?

thanks in advance as always guys...