BIG SHAFE

I am helping a friend put in his new head unit, but we have hit a brick wall. Let me first give some history so you have some background on the car.

Originally he had a old Pioneer radio that was stolen out of his car, the dash was ripped up, etc. Now I am trying to get his current head unit to work, Kenwood kdc mp425, but we have ran into a rather huge problem. The head unit was ordered from Crutchfield, along with the wiring harness and instructions. The first one we wired it up and had no power to the unit, it wouldn't turn on. I double and triple checked the 12V constant (always hot) and 12V ignition wires (hot when key is on) and all the fuses, including thorough inspection of the fuse for the radio.

I called Crutchfield for support and he suggested that I touch the power and ground wires to the battery, which we did and it still wouldn't turn on. He said the head unit was bad and I also couldn't think of another reason that it wouldn't turn on besides the head unit being bad. So we sent it back in exchange for another head unit.

Now, assuming that the new head unit was good, we hooked up the wiring harness and this head unit would not turn on. So before I try everything again, I'm looking for some help. I have a idea to put the ground wire on the chasis somewhere rather than in the harness, where there is a spot for it. I was also thinking that something happened to the wires when the old unit was stolen, but the constant and ignition wires are hot? Maybe there is something special with the Kenwood's I dont know about?

Thanks for you comments.

Big Shafe


Modified by BIG SHAFE at 2:52 PM 1/22/2005

fcm

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BIG SHAFE &raquo;</TD></TR><TR><TD CLASS="quote"> I am helping a friend put in his new head unit, but we have hit a brick wall. Let me first give some history so you have some background on the car.

Originally he had a old Pioneer radio that was stolen out of his car, the dash was ripped up, etc. Now I am trying to get his current head unit to work, Kenwood kdc mp425, but we have ran into a rather huge problem. The head unit was ordered from Crutchfield, along with the wiring harness and instructions. The first one we wired it up and had no power to the unit, it wouldn't turn on. I double and triple checked the 12V constant (always hot) and 12V ignition wires (hot when key is on) and all the fuses, including thorough inspection of the fuse for the radio.

I called Crutchfield for support and he suggested that I touch the power and ground wires to the battery, which we did and it still wouldn't turn on. He said the head unit was bad and I also couldn't think of another reason that it wouldn't turn on besides the head unit being bad. So we sent it back in exchange for another head unit.

Now, assuming that the new head unit was good, we hooked up the wiring harness and this head unit would not turn on. So before I try everything again, I'm looking for some help. I have a idea to put the ground wire on the chasis somewhere rather than in the harness, where there is a spot for it. I was also thinking that something happened to the wires when the old unit was stolen, but the constant and ignition wires are hot? Maybe there is something special with the Kenwood's I dont know about?

Thanks for you comments.

Big Shafe


Modified by BIG SHAFE at 2:52 PM 1/22/2005</TD></TR></TABLE>Did you try the new HU right at thr batt.? connect the red and yellow together and hold them to the batt.+ and hold the black to the batt.- turn the unit on, if it turns on the unit is ok if not , you have the same problem, [maybe the same Hu] although Crutchfield is one of the better online shops, if the unit powers up when you go to the batt. then the problem must be in the wireing, if you checked the powers and they are ok, check the ground and see if its ok, [BTW what are you using to test for power and ground?] 94

BIG SHAFE

Have yet try touching the wires directly to a battery, I was using a voltmeter to check if the leads were good. They were right at 12V.

fcm

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BIG SHAFE &raquo;</TD></TR><TR><TD CLASS="quote">Have yet try touching the wires directly to a battery, I was using a voltmeter to check if the leads were good. They were right at 12V.</TD></TR></TABLE> Did you also check the ground? The other thing I would check is the speaker wires, make sure that they are not shorted to ground or each other.

As for the ground, if its ok, use it, when you backbrace the HU to the OEM rear radio support you will get a very good ground, now the yellow constant power is another problem, Honda/Acura OEM HUs have a 7.5A fuse for the constant power, [found in engine bay fuse box] that is probably not enough for the Kenwood, [check fuse on Kenwood] on most of todays "highpower" HUs you need to connect the yellow constant to the batt., [ DO NOT just replace the 7.5A fuse with a bigger one] besides possable damage to wiring, it will not help to get more power to the HU amp, the best way is to run a 10ga, [fused at the batt.] wire from the batt. to behind the HU and connect the yellow to it, just like you would to an offboard amp, [although then you would use a bigger gage and run it someplace else] 94