1989 Jaguar XJS no pressure in rear brake lines

1989 JAGUAR XJS
80,000 MILES • V12 • 2WD • AUTOMATIC
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MICZYX
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  • 1 POST
Hello,

While pulling into a gas station I suddenly lost about 90% of my brakes. I stopped only thanks to swithcing to neutral and applying hand brake.
I had both the brake and abs lights on on vcm.
I checked the fluid level (appears to be normal), disconnected all the wires, cleaned them, and the warning lights are gone. After checking some more, I noticed that no pressure is coming to the rear (mboards) brakes. Any idea what should i check for next?

Thanks!
Mar 22, 2010 at 10:51 AM
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DAVE H
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POWER BRAKE UNIT
With engine running, apply brake pedal several times and check operation of pedal. If response is sluggish, check condition of vacuum hoses and unit air filter.
Turn engine off. Depress brake pedal several times to evacuate vacuum in system. Hold foot pressure on pedal and start engine. The brake pedal should fall under existing foot pressure. If pedal remains stationary, vacuum system failure is indicated.
BRAKE WARNING LIGHT
Check brake fluid level. Turn ignition switch on. Release parking brake lever. If brake warning light is on, disconnect electrical connector at switch. See Fig. 2 . If light is out, switch has operated.
If pressure differential warning actuator has operated, check for hydraulic fluid system failure and repair as necessary. Pressure switch should reset automatically during bleeding of brake system.
If light remains on check for short in brake warning electrical circuit or sticking reservoir fluid level switch. Repair short or replace reservoir fluid level switch as necessary.
Mar 23, 2010 at 4:34 PM