PowerBook 150 General Maintenance

Apple's exploded view of the PowerBook 150 (Service Source, PDF p. 120)

The PowerBook 150 shares the case of the PowerBook 145B but has its own logic board, IDE storage and PowerBook Duo memory. The take-apart steps are Apple's; the rest comes from owners.

Opening the machine

The PowerBook 150 contains static-sensitive CMOS parts; wear an earthed wrist strap.

1. Shut down with the Shut Down command, disconnect the adapter, slide the battery door open and pull the battery out using the door as a handle.
2. Remove the five T-8 Torx screws from the bottom case. Lift the top case, disconnect the interconnect cable, and lift the case off, unhooking the two tabs at the front.
3. When refitting, fold the interconnect cable the way Apple shows; a wrongly folded cable can short.
4. The inverter board comes off with its shield attached (Apple says not to separate them): two screws, then pull it straight up off the interconnect board. Set its brightness and contrast pots and the actuators in the top case to their extreme outer positions before refitting so they line up. bpadgett adds that the sliders move very freely when they have missed the pegs.
5. The logic board is held by three hex-nut screws and three Torx screws; the tall hex nut goes back in the corner nearest the RAM card connector.

Case and hinges

3lectr1cPPC considers the 150's plastics far worse than the other 100-series models': the hinge mounts fail and take the screw wells in the front bezel with them, and his own machine split around both hinges even after a 3D-printed mount was fitted. He advises not using the hinges at all until the mounts are replaced. Byrd has seen long splits in the mouldings of two machines, and Fizzbinn reinforced his standoffs with JB Weld epoxy. The metal shield in the bottom case rusts where a leaking battery has wetted it; Byrd's advice is to grind off the corrosion and paint it, as it holds parts in place.

Backup battery

Apple's developer note gives the backup battery as 2.4 V; it keeps the clock and parameter RAM while the main battery is out. Owners describe it as a soldered VARTA cell. 3lectr1cPPC's advice is to clip it out of every PowerBook 150, because it will leak and destroy the board it is attached to. One owner's had already leaked onto the logic board and destroyed choke L5 near the SCSI port. Without it, the machine may start as soon as the adapter is plugged in and sleep and wake erratically; MOS8_030 recommends fitting a new one. Apple's chart for lost settings points to the interconnect board first and the logic board second, and Apple's take-apart warns that the interconnect board contains hazardous materials. Clean any leakage off the boards as described on Battery Explosion, Capacitor or Corrosion Damage.

Main battery

The NiCad main battery is the same part, 661-0013, as in the PowerBook 140 family; testing and rebuilding are on PowerBook 140 Battery Replacement. Apple's handling advice for the 150 is the same: charge a new battery fully, do not leave it in the computer for more than two weeks without the adapter, and discharge and recharge it fully once a month.

Memory

RAM cards are PowerBook Duo cards. Apple's kit includes the card, an adapter, a brace and a screw: clip the card to the adapter by squeezing the white projections together without flexing the card, snap on the brace with its ridge between the rows of chips, push the brace legs into the two slots in the logic board, connect the adapter to J7 and fit the screw. Use Apple's logic board take-apart tool to disconnect the adapter. The largest card the 150 can use fully is 36 MB, for 40 MB in total.

Hard disk

The internal drive is a 2.5-inch IDE unit held by three T-8 screws. Only Apple's Internal HD Format utility can format it, and the utility rejects many drives. Owners' findings with CompactFlash cards in a 2.5-inch IDE adapter:

• Use a small card. croissantking puts the ideal at 1 GB or less and the maximum at 2 GB, and only with System 7.5.3 or later; Apple's utility cannot make custom partitions.
• The card must identify itself as a fixed disk. Fizzbinn found a Transcend 2 GB industrial card worked where 512 MB SanDisk and 1 GB Kingston cards did not.
• A card or drive formatted and partitioned in another Mac can be used directly: MikeatOSX prepared cards in a PowerBook 2400c, and 3lectr1cPPC formatted his 1 GB drive in a PowerBook 1400c.

The PowerBook 150 has no SCSI disk mode.

Related pages

• PowerBook 150
• PowerBook 150 Troubleshooting
• PowerBook 150 Capacitor Replacement Guide
• PowerBook 140 Battery Replacement
• Hard Drive Maintenance and Repair