diyAudio (
-   Car Audio (
-   -   Rockford Fosgate T800-2 (

seankane 11th August 2012 08:32 PM

Rockford Fosgate T800-2
Hello everyone.

I have a Rockford T800-2 board number PC-4698-B.

I bought the amp broken intending on fixing it. However upon recieving it, the amp works great aside one issue.

The power led does not light up??

D23 is the board location, I removed the led but I think it is different than the D18 and the D21 led's for the thermal and protection.

I have two questions: what is the value of the led, and what feeds the power to the led?

When I removed the led and tested the pads with my meter, one pad has 0 vdc and the other pad has 52.1 vdc.

I thought 52.1 vdc is a little to much for a tiny little led????

Any ideas?

seankane 11th August 2012 08:40 PM

I found my schematic finally and HV+40 vdc feeds it but R70 and R71 are inline before the led and the other end of the led goes to ground.

I will check the value of R70 and R71 they should both be 3K.

The part number for the led in the schematic is SS-5142SM blue.

Is that the actual part number or is that the rockford number?

R70 and R71 are both within tolerance......faulty led?????

Perry Babin 11th August 2012 09:52 PM

If you need help, send me the diagram. I don't have a copy.

seankane 11th August 2012 11:40 PM

Just sent it to you Perry, let me know if you get it all ok. Thanks.


Perry Babin 12th August 2012 11:55 AM

The part number is a Rockford number.

IF I would have read it more carefully, I could have saved both of us some time. Yes, 50+v indicates that the LED is defective. I've been using the next larger LED package hoping that the larger package would help it run a bit cooler and last longer. Changing the value of the resistors would also work but may reduce the brightness too much. I think these are the ones I've been using (digikey):

seankane 13th August 2012 08:00 PM

Thanks Perry I have ordered some for stock, I will let you know how they work upon arrival and installation.

Perry Babin 13th August 2012 09:03 PM

You may need to use a lighted magnifying glass to see the markings. On the ones I received, there was a very small green dot marking the cathode. The old diodes had similar markings.

seankane 14th August 2012 07:54 AM

Thanks for the heads up, they shipped them out today should see them in a few days. I will re-post with the results.

seankane 15th August 2012 07:56 PM

Just got the parts today, but wont be able to put them in untill tomorrow. I do see the green line you were talking about. On the protection and thermal led's the green line goes to the negative side.

I am sure this one goes the same way. Let you know tomorrow how it goes.

seankane 15th August 2012 08:41 PM

Got s quick chance to solder in the new package size and it works great, thanks again Perry!!!

All times are GMT. The time now is 07:56 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio