Member Avatar for dogbreath077

I know the 1150's have a power jack issue, we've fixed a huge amount of them. The one problem we haven't figred out is this. After some repairs to the power jack, the laptop will run on battery, it says that it is charging BUT, it is actually running off the battery. If the laptop is started with only the a/c adapter and no battery, the power and battery lights flash quickly, and the power supply clicks, and so does the motherboard just below the CD drive. we know that there is something overloading, we just haven't been able to figure it out without any motherboad schematics. All the solder joints are good at the power connector, and all the traces are either good or have been repaired. we do this sort of repair to the a/c jack pretty often, but are sick of seeing this problem and not having a solution. If anyone has an actual schematic of the motherboard or a definite solution to this after-jack repair, then we'd love to see it.

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  • Latest Post Latest Post by matthew1985

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The symptom pattern described by — LED shows “charging” but the machine actually runs from the battery, and with the battery removed the adapter clicks and LEDs flash — is characteristic of the power-path/charger stage forcing the adapter into current‑limit or protection. In practice that means a switch‑mode charger / power‑path controller or its external MOSFETs/sense parts are failing, so the board refuses to take system power directly from the adapter. See a typical power‑path charger description. (digikey.in)

A compact, practical troubleshooting sequence used by repair techs: confirm adapter open‑circuit voltage at the jack and correct rating; measure B+ at the battery connector with the adapter plugged in; check VIN-to‑GND resistance for a low‑ohm short; use a bench PSU with current limiting or the “inject low voltage + observe heating” technique to localize the shorted device; inspect MOSFETs, the charger IC area, sense resistor and nearby passives for visible damage. These are standard checks before swapping ICs. (ifixit.com)

A note about the LVC14A mentioned by : the LVC14A is a small logic (hex Schmitt inverter) device, not a power regulator, so reflowing it often won’t cure a heavy‑current charging fault. The real fix is usually the charger/power‑path IC or the external MOSFETs and associated passives near the DC jack/battery rail — which is what other contributors found when the board was repaired. (nexperia.com)

Best practice for a definitive repair is to get the boardview/service manual to identify the charger IC pins (REGN/ACOK/CHG/BAT), verify voltages there, and replace the damaged charger IC or shorted MOSFETs with proper ESD precautions and rework gear. The adapter clicking on connection is a useful diagnostic: it usually means the adapter is tripping on overload because the motherboard is pulling the rail down. (scribd.com)

Recommended Answers

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Member Avatar for Jupiter 2

Does the input pwer example 19v 1.6a match the power cable specs? If not then a chip on the mainboards is fried.

Otherwise, the battery has been recharged too many times and is past its" use by" date.

Member Avatar for dogbreath077

We figured it out. The IC chip that regulates the power distribution was fried. We replaced it an now it works fine.

Member Avatar for Bonillarl

Dell 1150 powers off after10 seconds and only power light blinks.

Member Avatar for matthew1985

We figured it out. The IC chip that regulates the power distribution was fried. We replaced it an now it works fine.

I now have a Dell 1150 that has the same trouble. I have tried resoldering the power jack but it looked fine before had. I tried resoldering the LVC14A chip that has been recommended but the results are still the blinking front panel LEDs. So which chip did you replace to get the problem solved?

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