QuestionI have a 95 chevy cavalier and am replacing the old radio unit with a newer radio.I downloaded the harness information on wiring the unit with all the color codes for the wires , I folowed it exactly as shown but radio still does not power up .Can you help?
AnswerHi Mark.
Back to square one, should have used an adaptor harness, but anyway, horse bolted and all that stuff!
Does the radio work on another car?
Has the new radio got the std ISO DIN plugs?
Check the power to 12 v live and 12 v acc and earth, if you have these three and all fuses are ok it should fire up.
Then check for a blown fuse in the rear of the set, some have one.
Failing that remove the radio and your connections, (back to square one) and follow the text below, that sorts out 99% of problems unless you have blown the set up.
Good luck, Peter
Check out the car is NOT the problem first though, had many a customer change the radio to no avail when it was a simple fault on the car.
You will need a test meter set to 20vdc or a 12v lamp or test probe.
I run this test when working on a car where a previous owner has ripped the connectors out of a used car and the new owner is in the same boat as you so it cover all the basics and should sort you out. So armed with your 12v probe or test meter, some paper, masking tape and a felt tip pen, here ya go!
Speaker wires. (non-amplified) these are tested with a AA battery across a pair of wires and you will hear a 'pop' from the speaker,
These are normally twisted together in pairs (if you are lucky) and usually in a loom of their own before going of to the four corners of the car and are the same colour for each pair but one with a colour trace on, i.e. blue and blue/white, green and green/white.
Label it (e.g. left rear), continue until all four pairs are identified and labelled.
Earth one side of your meter or tester to a metal part of the car, probe each wire until you have a wire that is live all the time with the ignition OFF, label this ‘+30’.
Switch on ignition and redo test until you find another previously dead wire now live, this is ‘+15’.
Switch off ignition and switch on the side / park lights, repeat test until you find a third live, label this ‘lights’. Switch off the lights
You should now have two or three left. One will be earth, (usually black or brown); one could be to an amp and or electric ariel (usually blue or blue white) and one for phone mute if fitted. Clip tester to +30 and probe one of the remaining wires, if you have an electric ariel it will go up. Connect your DIN plug to the correct wires and jobs a good un’.
DIN connections are.
Speakers
Right rear -, right front -, left front -, left rear-,
Right rear +, Right front +, left front +, left rear +
Power block viewed from cable side
Phone mute (white),/ n/c, / ariel & amp (blue), /ignition (red)
N/c, / 12vlive, (yellow or orange), / lights, (various colours),/ negative (black)
The third, usually top, block is for accessories such as cd changers
