SW20 rear brake

[Stocky]

Hi I have adjusted the hand brake travel and replaced a cable but still can’t lock up brake properly to pass work.
Could it be a problem with the slave cylinder adjustments?

[GDII]

Seized caliper piston(s)?

Do you need the hand brake to lock up? They don't lock up at the best of times.
Are the cables even length? This can make one lock up.
Do both cables move freely?
You might need to reset the calipers and handbrake lever as per the Toyota service manual.

[Stocky]

Just need hand brake to hold. Won’t pass wof at present even though cables are all adjusted correctly. Mechanic thinks it could be the adjuster on the brake cylinder. Thanks for your help.

[mknz]

Just need hand brake to hold. Won’t pass wof at present even though cables are all adjusted correctly. Mechanic thinks it could be the adjuster on the brake cylinder. Thanks for your help.

SWs use a mechanism that's built into the calliper, they're self-adjusting (i.e you don't need to do it). If the cables have been adjusted and they're not broken nor stretched then it's likely that the piston has seized in the cylinder (they'll be a royal pain to remove). If the pistons are seized you'll need a full rebuild kit to replace the handbrake seals (because that's where the water comes in from).

[GDII]

The cables can also seize in the cable sheathing. The handbrake lever might feel tight but the cable isn't moving so the caliper won't activate.

What you can do to test this is see how far the caliper lever moves with handbrake lever movement. Then remove the pin off the end of the cable to the caliper lever. If the hand brake cable won't let the caliper lever all the way back then you might have problems. Make sure the cables move freely in the outer sheathing when did connected at both ends.