Pioneer deh-4600mp no output

10 posts / 0 new
Last post
Buntz
Pioneer deh-4600mp no output

I was listening to my radio the other day, way too loud of coarse. Then nothing. Thought it might be some kind of built in overheat protection so i cycled the power. still nothing. i pulled over, totally disconnected it and then reconnected it and still nothing. it appears to function normally except for no output. I guess my amp could be blown (inside the headunit) but would that take out all four channels? I have it apart and i see some voltage regulators on the left hand side. Could it be one of them? I havent checked to see if i get anything from the preouts yet. but im assumeing if i do, the problem is the power amp. can anyone tell me if im heading in the right direction?

Matt Whitlock
I find it hard to believe

I find it hard to believe that you'd blow all 4 amps at the same time. I'd check all shared components first. The voltage regulators are a good start.

Buntz
well all the amps are on one

well all the amps are on one chip, so thats why i might have no output at all, but i'll check to make sure im getting good power and signal to the power amp. and those arent regulators, once i had the board out and turened it over i saw ECB on ther solder side. guess they're transistors, a switching power supply maybe?

Buntz
well i hooked it up, checked

well i hooked it up, checked the preouts with an oscilloscope, and sure enough, theres an audio signal. so i checked the speaker outputs and i get an audio signal also, but it is of almost identical magnitude. so wtf does that mean?

Buntz
talked to my stepfather who

talked to my stepfather who is an electrical engineer and he said he was pretty sure its the power amp. i'm gonna swap it for one out of a deh-1100, a few less watts, but its free and the pin-outs are identical. also gonna use some thermal grease this time for little better cooling of the chip.

Matt Whitlock
Awesome! I'm glad you were

Awesome! I'm glad you were able to diagnose it. Keep us updated on how it's going, and if you get it working again. Don't forget to post some pictures of you working on it.

Buntz
Effing A'. I deffinately

Effing A'. I deffinately fixed it. I love that feeling; accomplishment. But yeah the power amp was blown, only really tested one channel, but i assume the other are working, find out tomorrow win i reinstall it. i'll get some pictures up or a link to some pictures or something soon

Buntz
Pictuers and such about this

Pictuers and such about this project:

http://www.antimatter.1l.com/howto/am...

soundman777
I am having a similar problem

I am having a similar problem with my Pioneer DEH 4600MP, but heres the thing. It works for a few months, and then it quits for a day or two, and then work for another couple months or weeks. I've had it go out on me about 6 or 7 times. It's like it need to cool down for a few days and then its happy again. Any thoughts to this phenomenon?

Doin12volt
This is a shorted speaker

This is a shorted speaker terminal or shorted speaker wire in the vehicle. If EITHER speaker terminal OR wire gets shorted to ground, the Pioneer amp will mute all output to save the amp, untl the ground is corrected. This could also be a bad speaker with the voice coil shorted.

The easiest way to find the culprit is:

Next time the audio cuts out, remove the deck - dis-connect ALL the speaker wires, then hook the speakers up, 1 by 1 - when you connect the BAD speaker (or wiring) the audio will mute out again.

 

Connect With Techlore