MacBook Air (A1237) - Switching on? -

Hello, I have a problem with Macbook Air.
A1237 late 2008
Core 2 Duo 1.86 GHz, 2GB 1067 DDR3
NVIDIA 9400M 256MB
TOSHIBA 128GB SSD
(Plate 820-2374-A)
It was not flooded or repaired.

The computer stopped turning on normally after pressing the Power button.

No green or orange LED of the Magsafe power supply after connecting (replacement power supply) previously was
Reset SMC and NVRAM has changed nothing. I suspect a damaged battery (it has 0.3v) will not charge. At the battery socket, the voltage of 3v sometimes changes to 8v. At the power input on the 14v motherboard.

After several attempts and combinations (detaching the disk, keyboard, battery)
I noticed that it can be run in a somewhat unusual way:

1. Connected power supply - no LED (with or without battery)
2. Hold Shift-Control-Option and power 10 sec, as for SMC reset (quiet and fast electronic sound can be heard, as if micro-short circuits)
3. Everything released nothing happens
4. Detachable power supply
5. Press the power and hold 10sec (as if we would like to discharge the electronics)
6. Holding the power, connect the charger
7. After 10 sec. released power and press again, Mac starts

Max. Fan speed
No battery detection on the system when it is running. No visible temperature sensors in "Mac's Fan Control"
In addition, the computer works normally.

In the coming days I will replace the power supply with the original battery with a different one and replace the MagSafe socket

I am asking for help or is it more the fault of a damaged motherboard? Charging system? Bridge?
Is there a cmos battery on the disc in this model?
Can I upload bios? (UEFI)
Is there a replaceable temperature sensor on the cable?

I will gladly send it for repair to someone who could help me

First you need to be sure that the battery is working, but after what you write it is not.
Apple does not provide the ability to modify the BIOS, much less upload. As far as I know there is a simple (literally) BIOS and the rest is on the disk with the system.
Diagram attached. I didn't find CMOS battery.
On page 46 there are temperature sensors.

From the power supply itself (without batteries) this model must work.
They have not used CMOS batteries since 2008.
This is not a BIOS issue
There are no sensors on the cable.

Yes, everything is correct, without batteries also starts

EDIT
I noticed the computer can be run much easier:

1.We hold POWER without a 10sec charger
2.Still holding POWER connect the charger
3.We release POWER and press again
The computer starts up

Is it possible to run the ATH Apple Hardware test in this model?

I hold down the D key at startup and D + Command and nothing happens.

I merged. RADU23

Quote:

Is it possible to run the ATH Apple Hardware test in this model?

Yes. ASD 3S130 version

All tests in ATH (diagnostic program) completed successfully (PASS)

I ordered a new battery (replacement)

After inserting and connecting a new battery, most functions returned to normal life
Mac turns on normally, the button is charging the battery (still no LED on MagSafe is on), the charger is a replacement. I will try to borrow an org.
The fan speed has dropped. The program can see all temperatures.

I am worried about the high temperature.
65-78 degrees. Pastes listed for Arctic Silver 5
What is the temperature range during the operation of the motherboard (Auto) fan in this Mac?

Quote:

65-78 degrees

This type is so because the cooling system in this model is weak (no thermally conductive tube). Under load, it can grow to 100.

Ok, the subject of temperatures is clear
The computer runs on El Capitan and there are two more problems:

- No serial number: "Unavailable" after clicking "This Mac"

- No charging (hovering over the battery icon) "No charging"
MagSafe is not lit, after all the threads on the charger slowly charged the battery to 100%

Insert the NS directly into the charge and load it with the programmer or via the AST_BBS program.
Original charger?

I will own the REPLACEMENT charger today

Can you please insert this program?
I only have versions of some "server"

AST_BBS_1_1

Thank you.
Unfortunately, I don't know how to run it.
What program to upload onto a pendrive (transmac?? But it's an iso image) to make it bootable and recognized by maca at startup and holding the C key?

Managed to
1. I have changed the .iso extension to .dmg
2. I uploaded to pendrive with the "transmac" program
3. On startup maca key "command"
I was entering the number from the bottom of the housing.

Thank you for helping Mac work, I give "helped"
Ps I'm still waiting for otg. The charger and topic will be completed (let me know about the further development of the case)

camil9 wrote:

I will own the REPLACEMENT charger today

Especially on Macs according to several people, this is the best way to solve problems, and if smc falls it's "full of happiness".
I recommend Luis Rossmann's films with youtube.
The charger must be original because saving on it can be very expensive.

Since then MAC is still working.
Only one problem left.
There is no MagSafe LED on the REPLACEMENT or ORIGINAL charger, and the message in the system after hovering over the battery icon remains unchanged "Battery charging does not take place"
On a turned off computer, the battery can charge after a full night.
Please help what can I do?

power supply detected in the system report?

Screenshot

well ... the power supply is not detected by SMC. For this it does not work properly. On medium pin what voltage?

Should it look like this?


for me it is like this:
1. Mass
2. 14.93V
3. There is nothing
4. 14.93V
5. Mass

There should be about 3 on pin 3 v V.

What I wrote above concerns the replacement power supply (where voltage on pin 3 is missing)
Previously, the original power supply was connected and there was no charging. Is the original power supply also missing voltage on pin 3?
Puzzle
I do not know what to do.

It does not matter if the replacement or the original, there must be 3V on 3 pins (without this the power supply will not be detected). Only 3V gives no power supply, but a laptop.

I understand that is something wrong with the laptop.
The diagram of this motherboard is attached.
I can ask for help, what may be suspicious, what to look for?

Quote:

what to look for?

U6990

Reset_Uk wrote:

Quote:

what to look for?

U6990

After the exchange, continue to do the same. The computer works with limited charging. Thank you all for your help. subject to close

Hello everyone. Apologies for my message in English but I cannot speak Polish.

I wanted to thank for this topic and contributors, I have managed to enter the missing serial number of my MBP and I can now use iCloud services, Facetime and iMessage.

Dziękuję Ci bardzo.