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PowerBook 150 Capacitor Replacement Guide

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A Sharp panel from a PowerBook 150 with its eight 3.3 µF capacitors outlined (MacDat; image from oldcrap.org)

The PowerBook 150 has no electrolytic capacitors on its logic board. MacDat lists the parts to replace as eight small surface-mount electrolytics on the LCD, one capacitor on the backlight inverter and one on the trackball, and notes that failing inverter capacitors can still upset the backlight and contrast after the LCD has been recapped.[1] Apple's Service Source gives no component values.[2]

Capacitor list

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PowerBook 150 electrolytic capacitors[1]
Board Value Count Type
LCD (Sharp or Casio MD800TT10-C1) 3.3 µF 35 V 8 Low-profile surface-mount electrolytic
Backlight inverter 47 µF 25 V 1 Radial electrolytic
Trackball 10 µF 16 V 1 Radial electrolytic

MacDat's text gives 3.3 µF for both LCD makers, but the label on its photograph of the Casio panel reads 33 µF 35 V. The owners who have recapped these panels on 68kMLA used 3.3 µF 35 V parts.[1][3][4] Read the markings on the old parts before ordering.

The PowerBook 150 inverter with its single 47 µF 25 V capacitor outlined (MacDat)

Choosing replacements

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The LCD capacitors are tiny. They are electrolytic cans in black plastic shells with both pads at one end, so they are easily mistaken for tantalums.[3] 3lectr1cPPC recommends TDK C1608X5R1V335M080AC ceramics, 1.6 mm long, which need tweezers and good eyesight to fit.[3] vetz used 3.3 µF 35 V tantalums in a 150 with no problems.[4] MacDat prefers tantalums to ceramics, because ceramics lose capacitance under DC bias and have caused contrast drift on some LCDs.[1] Through-hole parts will not fit; use surface-mount types, mounted at an angle if their terminals are at opposite ends.[3]

Procedure

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  1. Shut down, disconnect the adapter and remove the main battery.[2]
  2. Remove the two plastic plugs and the two T-8 bezel screws. Pull the bezel down and away to free it from the tabs at the top and sides.[2]
  3. Cover the keyboard with a cloth. Remove the four T-8 display screws, lift the display out of the housing and EMI shield and lay it face down.[2]
  4. Pry up the display cable connector with a small flat-blade screwdriver, then disconnect the inverter cable from the backlight cable.[2]
  5. Remove the old LCD capacitors, clean off all residue and fit the new parts, observing polarity. If the capacitors you remove all test good, look elsewhere for the fault.[3]
  6. For the inverter, remove the top case (five T-8 screws, then disconnect the interconnect cable), take out the inverter's two screws and pull it straight up with its shield attached; Apple says not to remove the shield. Replace the 47 µF capacitor.[2][1]
  7. Refit the inverter with its brightness and contrast pots and the top case actuators at their extreme outer positions, and route the inverter cable as Apple shows so it is not pinched.[2]
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References

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  1. ↑ 1.0 1.1 1.2 1.3 1.4 MacDat, "Capacitor Reference - PowerBook 150" (retrieved 2026-10-02). No electrolytics on the logic board; LCDs from Sharp and Casio both use eight 3.3 µF 35 V low-profile surface-mount electrolytics; inverter 47 µF 25 V radial electrolytic; trackball 10 µF 16 V radial; failing inverter capacitors can cause inconsistent backlight and contrast after the LCD is recapped; tantalums preferred to ceramics on the LCD. Secondary source.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Apple Computer, PowerBook 150 Service Source, hosted here as File:PowerBook 150 Service Source.pdf (see PowerBook 150 Service Source). PDF page numbers: Main Battery pp. 43-45; Top Case pp. 46-48; Inverter Board pp. 66-68; Display Bezel pp. 82-84; Display pp. 89-92; Exploded View p. 120. Module-level only; no component values.
  3. ↑ 3.0 3.1 3.2 3.3 3.4 68kMLA forum thread "Powerbook 150 - Display Issue", January 2022. 3lectr1cPPC and mdeverhart: the LCD capacitors are small electrolytics inside black plastic shells, with both pads at one end, often mistaken for tantalums; 3lectr1cPPC used TDK C1608X5R1V335M080AC ceramics (3.3 µF 35 V, 1.6 mm long) on a 145 and recommends them; SunkenShjips: 3.3 µF 35 V. Community repair report.
  4. ↑ 4.0 4.1 68kMLA forum thread "Only half of screen showing on PowerBook 100", December 2025. vetz: used 3.3 µF 35 V tantalums (Mouser 581-TAJB335K035SNJ) in a PowerBook 150 with no issues. Community experience.


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