In the HJ series the brake fail & handbrake shared the same warning light & therefore only needed a single wire. This is the tan wire at position 'H' in the 11-pin plug. Pin 'J' was vacant in HJ.

For HX-WB they had 2 separate lights so the tan wire (pin 'H') was used for the brake fail light & they added a new yellow wire to pin 'J' for the handbrake light.

If you're using an HJ cluster in a later car just join the 2 wires together in your body harness & connect at pin 'H'.

Dr Terry