HP Envy 17-ce009nf laptop that won't start

[Christian0734]

Hello, I have an HP Envy 17-ce009nf laptop that won't start, consuming about 0.035 A with the power light briefly flashing every 4 seconds or so. Any ideas? Thank you.

[mon2]

Re: HP Envy 17-ce009nf laptop that won't start

Post the silk screen markings of the logic board which may lead to a schematic in this forum. If you have a schematic, post only in the schematic forum and reference it here.

If the adapter is the original, likely the fault will be in the first 2 DCin mosfets but start with the voltage to ground measurements starting at the DC in power jack. It should be ~19 volts.

Next, review the nearby 2 * DCin mosfets (8 pins each) which will be driven by the charger IC. We are interested in the topside markings of these mosfets and the charger IC. The charger IC is likely the TI BQ series but need the topside markings.

As per the above sticky by @Piernov - often the dcin mosfets get nuked and the logic board is no longer able to receive the power adapter voltage.

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

Additional information, there is a new battery; when the charger is plugged in, the charging light starts to flash after about a minute.

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

Post the silk screen markings of the logic board which may lead to a schematic in this forum. If you have a schematic, post only in the schematic forum and reference it here.

If the adapter is the original, likely the fault will be in the first 2 DCin mosfets but start with the voltage to ground measurements starting at the DC in power jack. It should be ~19 volts.

Next, review the nearby 2 * DCin mosfets (8 pins each) which will be driven by the charger IC. We are interested in the topside markings of these mosfets and the charger IC. The charger IC is likely the TI BQ series but need the topside markings.

As per the above sticky by @Piernov - often the dcin mosfets get nuked and the logic board is no longer able to receive the power adapter voltage.

I have all my voltages, everywhere on the coils. And the fan starts up at the same time as the light comes on, but it lasts 1 second, then 4 seconds later it does the same thing.

[mon2]

Re: HP Envy 17-ce009nf laptop that won't start

Remove all power -> measure the resistance to ground of each coil. Checking for a low resistance which will result in a heavier than normal current draw and the local rail will then power cycle. This is one case.

Could be a corrupt bios - not my area so do wait on others to comment.

Does the unit power on and stay on with the battery (only)?

What is the history of this unit?

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

For the battery, it's hard to say. The client changed the battery, and from what I understand the computer worked until the battery ran out. Currently, it is empty and does not recharge. I also think of a corrupted BIOS but I wanted to have several opinions before desoldering the EPROM. There are no power supply issues, I have no short circuits, I have all my voltages on the coils. What else?

For the history, the client replaced his internal battery because he had an error message regarding the battery. From what he tells me, the computer worked with error messages sometimes that he could not describe to me, and finally, it ended up stopping and not starting again

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

I have the coils of the CPU power lines at 2.1 Ohms, but I think the value is correct. Anyway, it's clear that it tries to start and then interrupts at the very beginning of the Power-On Self Test.

[mon2]

Re: HP Envy 17-ce009nf laptop that won't start

Ok - review the battery connector. The details of the battery are communicated over the SMBUS (aka I2C) interface. Measure the voltage to ground of each pin on the battery connector.

Specifically interested in the SCL / SDA voltage measurements. If either of these 2 pins are stuck - then the SMBUS communication cannot occur and also cannot charge.

Do you have the details of the silk screen of the logic board or even better if you have a schematic (but do not post it here).

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

On the two red wires I have my 19.5 volts, on the white wire I have 2.65 v and on the brown and yellow wire I have nothing at all.

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

For the motherboard reference, I am currently peeling off a paper sticker that they put on it

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

Okinawa 17 2G MB
18795-1
448.OG812.0011

[mon2]

Re: HP Envy 17-ce009nf laptop that won't start

How many contacts are on your battery connector?

Remove this battery and measure each contact pin again. Checking to see if the battery causing the SMBUS lines to tank or is it the logic board?

Review this thread:

https://www.laptopu.ro/community/pin...-batteries/hp/

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

On the brown wire of the connector, I have 0.4 volts

8 pins, 2 red; 2 black, one brown, one yellow, one white

"I'm not talking about the battery connector but the power connector, the link you gave me refers to the battery connector.

On the 8-pin battery connector, from left to right: 0v; 0v; 2.7v; 3.2v; 2.9v; 1.0v; 3.2v; 3.2v

When the battery is in place, between the negative and the positive (pin 1 and pin 8), I indeed have about 15 volts.

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

Important information, I resumed testing this morning, if I inject 13 volts on the + and - terminals of the battery connector
(with or without the battery connected), the computer starts up without issues, with normal display on the HDMI port!


I should also clarify that I am testing with two different original HP power supplies. And as soon as I no longer send current to
the terminals of the battery connector (With the lab power supply set to 13 volts), the computer stops and I find myself again with the power light flashing briefly once every 4 seconds. Another
detail: when I connect the battery (whether it's the new one or the old one), after a few tens of seconds, the light of the connector that was orange switches to a fast white flashing.

[Stevedb]

Re: HP Envy 17-ce009nf laptop that won't start

I think the problem is in your dcin mosfets . How much voltage do you have on the gate and also how much voltage on ACDET off the bq chip. Which charging ic do you have and also provide high definition pictures.

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

Thank you, now I'll have to find the schematic or the boardview, this board is not simple at all.

[mon2]

Re: HP Envy 17-ce009nf laptop that won't start

For now, the schematic is not required.

Start with the DCin power connector and clear post pics of the top and bottom side of this region of the logic board.

After the DCin connector will be the 2*DCin mosfets (8 pin) and these mosfets will be driven by the charger IC (often is the BQ series by Texas Instruments).

Post the topside markings of each of these parts - the mosfets and the charger IC.

With a multimeter, the topside markings of these parts and your eyes, we can review the position of this faulty logic board.

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

In fact, I have a big problem, I made a mistake. I had placed my two current injection probes for tests on the battery connector (13 volts) nearby. A little later, I wanted to measure the voltage on the fuse that we see in photo 3 and, due to a lack of attention, I picked the wrong probe. Instead of taking the one from the multimeter, I took the one from the power supply! The result: a short circuit, the 3v/5v chip we see in photo 4, PU4501 ((1285B), is in a short circuit. With the thermal camera, it heats up to 100° (I have nothing else that heats up) and the board's power consumption in standby mode is about 0.250 A. Moreover, it is difficult to see on the motherboard the main Vin 19v line, I can't even find the shunt resistor.

In the photo below, we can see two capacitors. This part of the board is short-circuited. After taking the photo, I removed them, but it's still short-circuited.

[Christian0734]

Re: HP Envy 17-ce009nf laptop that won't start

The second photo is a duplicate, here is the correct one.

[mon2]

Re: HP Envy 17-ce009nf laptop that won't start

What are the top side markings of PU4401 ic in this last picture? This is the square ic with pins on each side and close to the memory socket.