Battery power leaks to MagSafe input

I have MacBook Air which was damaged by spilled drink. After that system was completely dead. Battery was left connected for a long time after incident.

I was able to clean the logic board with alcohol, Now it starts and runs but oddly:

  • If battery disconnected, runs from charger normally
  • If battery connected, runs from battery normally
  • If charger connected and light green, and then I connect battery, all works normally, and battery charges

But! If battery connected, and then I try to connect charger, nothing happens - light on MagSafe won’t light, system can’t see charger completely.

I think the problem is because I have constantly 4.7 volts on MagSafe input, and charger as soon as detects this voltage, shuts down to safety.

Am I right? how battery currency shuts off from outside world?

I’ve seen 1v on Q7155 4th pin in both cases, from battery and from AC is it normal?

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2889612:0crwdne2889612:0 0

crwdns2944067:08crwdne2944067:0:

What was the drink you spilled? And what kind of alcohol did you use to clean the logic board? Did you take the logic board fully out?

crwdns2934271:0crwdnd2934271:0crwdne2934271:0

Answering Dan's questions: I did not spill anything. Judge by the smell that was champagne. I cleared it with ethanol (with logic board fully out) Board fully cleared now, just take it as granted.

By the way, I do not think Q7155 is culprit. I just can't find the detachment point where system power disconnects from charger power (if such point exists)

crwdns2934271:0crwdnd2934271:0crwdne2934271:0

Well, maybe you didn't do it ;-}

But, clearly champagne is a drink which has sugar, acids & alcohol within it.

Ethanol is not what I would have used.

Time to start again, take the logic board out and this time use distilled water to clean it I would use an ultra-sonic cleanser if you have access to one that the board will fit into. Otherwise, let it sit a bit and then change to water a few times, then use reagent grade 85% isopropyl alcohol to wash the board once more. The water will dissolve the sugars and neutralize the acids. The isopropyl alcohol will help in removing the water thats seeped under the chips. let the board fully dry on a warm sunny window sill.

crwdns2934271:0crwdnd2934271:0crwdne2934271:0

Warm sunny window sill. In Russia. At winter. You must be joking:)

Actually I will try that as soon as I get my hands on 85% isopropyl.

But first of all I need answer to this simple question: should the voltage be presented on magsafe connector of unonnected macbook?

crwdns2934271:0crwdnd2934271:0crwdne2934271:0

No, you have a leakage issue. This is where the conductivity of the spill/corrosion is interfering with the MOSFET's switching within the power circuit.

Да подоконник будет холодным, но солнечные лучи теплые!

crwdns2934271:0crwdnd2934271:0crwdne2934271:0

crwdns2934275:03crwdne2934275:0

crwdns2934285:0crwdne2934285:0