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Hi Guys
I'm new here.
I 've been repairing computers for a long time. I just recently ran into a laptop that had a bad power adapter connector on the motherboard. While replacing it a surface mounted component labeled RV1 came off the motherboard and quickly disappeared.

Any ideas on what type component RV represents?

There is a second component labeled rv2 near by.

The laptop works but doesn't detect that the battery is plugged in now. a problem which I believe didn't exist before the repair.

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Dani AI

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Short expert summary and next steps anchored to the thread: reported RV1 coming off during a DC-jack replacement and then the system stopped recognizing the battery; reports the same symptom on a similar Inspiron; correctly asked for the exact model. On PCBs the prefix "RV" is commonly used for varistors (voltage‑dependent surge clamps) so that footprint is very likely a small transient‑protection device sitting at the adapter input. (en.wikipedia.org)

What those tiny SMD surge parts look like and why the rating matters: modern manufacturers make multilayer SMD varistors in 0603–1206 style packages with specified continuous operating voltage, clamping (breakdown) voltage and surge‑energy ratings. For a 19 V laptop input you must match the device family and continuous voltage (do not fit a very low‑voltage clamp). Datasheets show package sizes and the relevant operating/clamping specs to pick the correct replacement. (bourns.com)

Simple, safe identification/tests (power OFF where directed): visually compare the footprint to nearby known SMD diodes/filters; measure with a DMM: an SMD varistor usually reads open/high resistance at low DC, a TVS diode will show diode behavior in diode mode, and a PTC/polyfuse will show low ohms. With the board powered (and careful) check that the adapter delivers ~19 V at the jack and that the charger/ID lines around the battery connector show their expected voltages—missing or clamped rails are a diagnostic clue. Use ESD precautions and avoid powering the board with a suspected short in place. (kynix.com)

Replacement and follow‑ups: match package, continuous DC rating and surge specification from a vendor datasheet and reflow/solder carefully. Do not substitute a low‑voltage clamp (for example a 5 V part) on a 19 V rail — it will conduct and disrupt the rail or damage components. After replacement verify adapter voltage, battery‑sense/ID voltages and that the charging/PMIC area sees normal values. If battery recognition still fails, next checks are the charging IC, input MOSFETs and any series polyfuse/sense resistor. Application notes and varistor selection guides explain the “continuous voltage + margin” rule and surge energy specs. (next.gr)

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What's the model of the system?

Member Avatar for Beaver Newby

It is a Dell Inspiron i1200.

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Thanks Guys

I think thats it!! hmmm, a "Metal Oxide Varistor" I have search high and low for one for on another scrap circuit board. no luck??

Digikey.com seems to have a surface mounted component just like it, but I have no Idea about the voltage rating or capacity. The ones they have are rated 5 volt and several amps. The power supply is 19 volts 3.1 amp DC.

They are small!!!I have tried putting the laptop back together with out it and now the battery is not recognized?

I just had another dell laptop come in which has had liquids spilled on it. I will get to see if it follows the same circuit design. It is not scrap at this point so I won't be able to rob it if it follows the same circuit design. yet!!!

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