Fender Rumble 500 Bass amp I only hear the fan nothing else ?

[Jam]

I have a Fender Rumble 500 2x10 combo amp. The only thing I get is I hear the fan run. The power light on the amp don't light up and no sound and the fuse is good on the Icepower Amplifier? Thanks for any help thanks

[The Dude]

Do you have a schematic you could post?

[Jazz P Bass]

Hah.

That Ice Power is such a joke.

No support.
No info.
Cannot be worked on.

All that you can do is purchase a new one.



Close as I can get is the 350.

Rumble_350_2010_schematic_Rev-B.pdf

[Jam]

Is their a way to test the Ice Power to make sure it's the issue? The Ice power is $200 wow

[Leo_Gnardo]

Have you opened up the amp, had a look inside? Last year I had a smaller version of this, one of the multipin connectors from power supply to amp wasn't seated properly. It was cocked at about a 20 degree angle, sloppy work at the factory. Once I squared it up the amp ran perfectly. Takes just a few minutes to peek inside, who knows maybe you'll find something similar.

[Jam]

So I ordered a new Ice Power board and I hooked everything up and still get nothing and I checked connectors and everything look seated right? Any idea? Thanks for any info

[MarkusBass]

If the fan works, it means that the power supply in the module works. Only the power amp is not working because most probably it is disabled. The power amp is disabled when a plug is inserted into HEADPHONE jack, or the headphone jack has failed. Have you check the jack? You can also measure the ENABLE voltage on pin #2 of the P102 connector.

Mark

[J M Fahey]

Leaving now, but just for starters:
1) post here th correct IcePower datasheet, to know pinout and what is expected at any of them
2) earlier the fan did run, does it still?
That woukd show that the module is at least basically working.
3) with amp off and unplugged from mains, measure continuity from module speaker out pins, plug a speaker cable and check that free pllug tip and body have continuity to Ice modue speaker outs , which I guess is run bridged
4) IF confirmed, turn amp on/off a couple times, with ear close to speaker: hear *anything* ... plop/hiss?
5) SHOULD HAVE BEEN #1 : did you check speakers and speaker cable????
6) will wait for datasheet to suggest injecting audio 8even a fingertip) straight at the Ice module input.

[Jam]

Thanks, I having a hard time finding Ice power data sheet but I do still have the fan coming on and I do hear a noise when I turn on and off the amp from the speaker. I don't know if I did it right but on #2 pin of p102 I get -0.540 VDC with headphone plugged in and I get -0.117 VDC with nothing plugged it.

[Jazz P Bass]

Can you try that measurement again with P102 removed?
Take a measurement of the ICE module itself.
Use pin 6 or 7 for a ground reference.
According to the ICE 'datasheet', pin 2 is held at +5 Vdc internally when unconnected.
icepower125asx2_Mute pin.pdf

If the 500 is anything like the posted 350 schematic, there is not any negative voltage source on that circuit.
-rumble_350_mute circuit.pdf

The 'mute' pin, according to Fender, should be +5 Vdc with no headphone connected (unmuted).
With a headphone inserted it should read 0 Vdc.
(which agrees with the ICE datasheet. The Fender circuit should do nothing to pin 2 (which should sit at +5 Vdc) until a headphone is plugged in. Then the circuit will pull pin 2 to zero volts, thus muting the speaker.)

I have a feeling that Q9 FET is shorted.

[Jam]

Ok thanks when I unhooked p102 and I read pin 2 and 7 on the ice power module I got -1.475vdc

[Jazz P Bass]

I would send an email to ICE.

[Jazz P Bass]

Out of curiosity, I would try to measure the resistance of the amp header, pin 2, to ground. (disconnected from the ICE module)
Where R 97 & C 68 meet.
Or if you can get at it, simply measure across C 68.

Alternatively, what is the voltage at pin 2 (disconnected at the ICE module)? (The voltage that the Fender circuit is sending to the module)

Something is not right.

Note: have you checked the voltages on P 103?
Should be + 24Vdc and - 24Vdc.

[J M Fahey]

Agree and add: have we tried to inject some audio straight at the ICE module input?
Maybe it works but no signal is reaching it.

[Jazz P Bass]

That may be difficult.

The module uses a differential input.