Marantz NR1501 HDMI Board CHK CPU Error

[Foppel]

Dear all,

i need help with a Marantz NR1501 Audio Receiver. The displayed error message was CHK CPU. The analog Audio Part is working, the digital audio part not. The Service Manual says that some voltages on the HDMI Board are not correct. I checked the voltages on the CN1101 connector:

5V to GND -> 4,95V
3V3 to GND -> 12,7V

My question is why do i have 12,7V on the 3V3 Pins? Maybe a shorted Q215 on the Mainboard? What is the function of the Q215 transistor on the Mainboard?

The reading of the output from the both Buck Regulators AOZ1021AI:
IC1007 to GND -> 4,05V
IC1006 to GND -> 0,66V

I am really frustrated. Many thanks for your support. I extracted some pages from the Service Manual. Please let me know if this is not correct then i will delete it.

[tibimakai]

Re: Marantz NR1501 HDMI Board CHK CPU Error

You should look up those ICs datasheet and see if those voltages are correct.

[Foppel]

Re: Marantz NR1501 HDMI Board CHK CPU Error

I powered up the HDMI Board with 5V from my lab power supply limited to 500mA. Then i recognized a warm/hot AK4588 IC1501 CHIP. I ordered a new one from china and changed the AK4588 but i still have the same error. The new chip will also heat up and the voltage will drop. I desoldered the chip and connected 3,3V and GND directly to the IC. But still the same. The chip heat up and get hot in a few seconds.

The question is: Do we have a defective IC AK4588 or is it related to another part?

The AK4588 datasheet can be downloaded here:
http://www.akm.com/akm/en/product/da...artno=AK4588VQ

many thanks to all - Foppel

[Khron]

Re: Marantz NR1501 HDMI Board CHK CPU Error

Going by the datasheet, a rough total of the power consumption of that chip alone is in the region of 160-some-odd mA, when supplied at 5V, comes out to ~0.8 watts: at 3.3v, it's still north of 0.5 watts. In one of those flat packages, with not a lot of heatsinking capability, it's quite normal that it's gonna feel warm (if not even hot) to the touch.

Actually, do you have a multimeter with a thermocouple, or some way to measure the temperature of that chip? And also, what's the current consumption of the whole board, on the 5v and 12.7v rails, with and without that chip?

That 12.7v on the 3.3v rail (which is technically "3V3_IN") seems like it is what it should be - on the schematic i see two 8-pin switching regulators which put out the 3.3v for the various chips on the HDMI board.

The 4.95v you measured on the 5V rail is well within the usual 5% tolerance, so that shouldn't be a concern.

[Foppel]

Re: Marantz NR1501 HDMI Board CHK CPU Error

Hi Khron666,

thanks for your posting. If i desolder IC1501 AK4588 then the power consumption of the board is around 70mA at 5V. The KIA7805API has a maximum ouput current of 1,5A at 5V. Is it possible to test the AK4588?

I think the polish guy has the same problem:

http://www.elektroda.pl/rtvforum/topic2722389.html

I think after he changed the AK4588 the device is working again.

P.S. I also changed the transistor Q215 on the main board but nothing changes.

I think the HDMI Board is a common problem with this devices:

http://www.audiokarma.org/forums/sho...d.php?t=560331

many thanky in advance...

[stj]

Re: Marantz NR1501 HDMI Board CHK CPU Error

a 7805 will not give even 1a without a very big heatsink.
and they have a thermal diode in them that will cause a volt-drop if they get too hot.

[Khron]

Re: Marantz NR1501 HDMI Board CHK CPU Error

To be totally frank, getting "advanced" chips from China, imho, should be considered a "no other choice left"-scenario.

I'm beginning to be slightly suspicious of those electrolytics on that board, though. A few months ago i had a client with an Onkyo receiver that had a wonky digital / HDMI board, and replacing the caps on the supply rails brought it back to life. I see three Teapo SEK(?), and those two on the edge have a colour scheme that reminds me Panasonic FC, but what are they?

[Foppel]

Re: Marantz NR1501 HDMI Board CHK CPU Error

OK now im sure it's not the AK4588. The problem was the missing ground at AVSS PIN 56. If i connect this PIN to GND the power consumption is about 100mA and i think this is OK. But i still get the Error CHK CPU. I tested all the caps near the regulator IC's but they are OK. I also checked the DATA and CLOCK Lines between the Main and Sub CPU. How can i test I2C communication? Does it work with an Arduino? I can not find the Datasheet of this IC1401 (M3030RFEPFP). I think i will resolder the CPU and SUB_CPU. The problem is i can not find the firmware for this device.

For CHK CPU the service manual says:

Indication of communication error between main CPU
(MAIN PWB/IC102) and sub CPU (HDMI PWB/IC1401)
● Points to be checked
1) Voltage of main CPU (MAIN PWB/IC102) and sub
CPU (HDMI PWB/IC1401) is supplied properly.
- 3.3V SUPPLY : IC102 (MAIN PWB), IC1401
(HDMI PWB)
2) Oscillation of two CPU is normal.
- IC102 (MAIN PWB) : 16MHz
- IC1401 (HDMI PWB) : 16MHz

The 3.3V power supply is working and it's connected with the two CPU's. The main CPU will get the power from StandBy Board. The Sub CPU from IC1007.

@Khron666 The Caps are all from SamWha. I replaced some of them with high ESR. I have a scope at my work. Should i test the output of the voltage regulators for ripple current?

Thanks in advance - Foppel

[CapLeaker]

Re: Marantz NR1501 HDMI Board CHK CPU Error

So what happened with the 12V on the 3.3V line after removing the chip? Is it back to normal?

[Khron]

Re: Marantz NR1501 HDMI Board CHK CPU Error

That 12v seems to be normal, since it's the INPUT to the two (switching) 3.3v regulators on the HDMI board. It comes from a winding on the transformer through a plain ol' bridge rectifier.

Can you measure the supply voltages for / around the cpu's that the service manual indicates? I'm quite sure the pinout is on the schematics, or at least you can find the (ceramic) capacitors that are filtering those supply rails. Ripple might be worth checking - if those electrolytics are unsuitable (or dead/dying), they may well be the ones screwing things up.

[Foppel]

Re: Marantz NR1501 HDMI Board CHK CPU Error

Hmm i checked all the caps and resistors near the CPU's but they are all correct. But at the IC1401 the 10nF Caps are a bit low. I get the following results:

C1405 8,5 nF
C1406 8,7 nF
C1407 8,7 nF

At the IC102 i get the following:

C261 10 nF
C262 11nF
C263 11nF

Will it help to change the caps at IC1401? I think i will give up soon. The last thing i try is to power up the 3,3V from my lab power supply and check all the VCC Points near the CPU with an old Tektronix scope

best - Foppel

[Khron]

Re: Marantz NR1501 HDMI Board CHK CPU Error

If you'll read my last message (more) carefully, you'll see i was asking about the voltages I just mentioned the caps because it's easier to poke a multimeter probe at their terminals, rather than the tiny pins on a chip.

[Foppel]

Re: Marantz NR1501 HDMI Board CHK CPU Error

Thanks Khron666 for the hints. I checked all the caps but they are all good. I also use my scope to check for ripple but nothing. Everything was OK. But i have a little pump at the oscillator XTAL1301 from the IC1301. Do you think it is related to the problem? Thanks in Advance:

Here is the Video from the scope:
https://www.youtube.com/watch?v=0qMo0UUIYgU

best - Foppel

[tibimakai]

Re: Marantz NR1501 HDMI Board CHK CPU Error

I'm reading about these(different brands) receivers in general, and many seemed to have issues with the DSP IC soldering issue.
This seems to be pretty wide spread problem in the electronics world. This issue is in laptops with graphics chips, PS consoles, TVs, receivers.
What is going on here? These companies, don't know how to solder a chip?

[Foppel]

Re: Marantz NR1501 HDMI Board CHK CPU Error

If i remove the Video Board and go into service mode the device shows me CHK DSP. And the HDMI Firmware Version will be displayed. When i reconnect the Video board i still get the error CHK CPU and the HDMI Firmware Version is not displayed. I think the sub mcu IC1401 is ok. When the device is powered up the output 26 is high and will enable the 3.3V power regulator IC1006. I will measure the communication ports at the Connector CN1003 9-16. But i think the source of the problem is the IC1301.

I have only 7.5V at the 9V power regulator output of the IC205. Maybe this is the problem?

best regards - Foppel

[stj]

Re: Marantz NR1501 HDMI Board CHK CPU Error

well that's a problem.
but you need to find if the output is bad, or if something it powers is drawing to much current.

[CapLeaker]

Re: Marantz NR1501 HDMI Board CHK CPU Error

something should get warm if it draws a 9V line down to 7.5V. If you have a real good Ohm meter with lots of numbers on the display, or a leak seeker, you should be able to trace the fault to the dot, since you got something to go from now if the line is getting drawn down by a shorted component.

[Foppel]

Re: Marantz NR1501 HDMI Board CHK CPU Error

Thank you CapLeaker. But it was not the wrong voltage. I just used the wrong Ground. Now i have 9.05V at the 9V voltage regulator. I think something is wrong with the grounding. AVSS from AK4588 should be connected with the GND from IC205. But then the AK4588 will get hot in a few seconds and the voltage at IC201 is dropping down to 2.xxV. If i connect the AVSS to the GND from the IC201 the 5V Rail is stable at 4.95V. Sometimes the firmware information will be displayed sometimes not. I have the following firmware:

Menu + Cursor right (5 Seconds)

NR1501/N
090921-1
DA 8,7
DSP
HDMI 09062818
CHK DSP

Normally at DSP the DSP ROM Version is displayed. In my case nothing is displayed after the word DSP. I think the DSP firmware is located in the IC1601.

[mg37]

Re: Marantz NR1501 HDMI Board CHK CPU Error

I've been working on two NR1501's for a few days now, with different defects.
One had similar problems with digital signals. Analog signals only worked with Source Direct enabled.
I discovered that when heating up the HDMI board with a hair dryer digital HDMI and analog normal signals are working again. Cooling one part of the HDMI PCB, the HDMI audio stopped and eventually all HDMI signal went dead.

On both receivers I've discovered pretty strange behavior with a 1.8v regulator on the HDMI board. Its IC1606 (in the corner, near the connectors on the right)
This regulator was oscillating and gave me an approximately 1.5v DC with AC on top of it.

According to the datasheet of this IL1117-1.8v regulator an output capacitor with a ESR of not more than 0.5 Ohms is recommended.
I looked up the capacitor on the diagram, its C1604 on the component side of the board.
This capacitor had on both HDMI boards an ESR way above 0.5 Ohms. One had 12 Ohms, the other was 15 Ohms.
So I replaced the capacitor on one HDMI board with a normal radial electrolytic capacitor of 100uF/16v.
Now the unit is playing perfectly all analog and digital signals.

Hope this helps you or any other that is trying to fix a NR1501.

[Foppel]

Re: Marantz NR1501 HDMI Board CHK CPU Error

Hi @mg37,

thank you for the reply. I also changed the caps near IC1606 but in my case nothing changed. But it will help if you have a disgusting noise at cold start, see: http://www.avsforum.com/forum/90-rec...thread-12.html

In my case something with the grounding was faulty. Sometimes the 5V rail from the Mainboard will geht down to 2V! I spended so much time for repair, but in the end i sold the device on Ebay. I spoke with a polish guy. He has the same problem with two of these devices. The problem is the logical part. It is too complex to fix anything.

best regards - Foppel