Cadillac Repair: 89 Cadillac DeVille, release vacuum, vacuum line

Question
89 Cadillac Deville Parking brake does not release when shifting out of Park or Neutral. Manual release works OK. All other features in the automobile work normally. What should I check to isolate problem?  
                   Thanks
                   J Luna

Answer
Look up under the dash, You will have to remove the black plastic cover access panel in order to see the steering column of where you will see a vacuum opaerated mechanical switch located on the steering column that has 2 vacuum lines attached to it. One is a constant source of vacuum when the engine is running and the other has NO vacuum until you put the gear lever into DRIVE or REVERSE of which then allows vacuum to the other vacuum line of which goes to a small vacuum canister mounted to the emergency brake device of which pulls a rod in oreder to disengage the lock mechanism of the emergency brake.

Im most cases the vacuum line to the emergency brake canister has become disconnected and simply needs to be reattcahed. This usually happens when someone accidently knocks it loose when working under the dash area.

However, It could also be a faulty vacuum switch on the steering column or a faulty canister release vacuum valve at the emergency brake mechanisn or a faulty vacuum line from the engine to the vacuum switch or a faulty vacuum line from the switch to the vacuum canister at the emergency brake mechanism.


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