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Maximum Isc Extension - Deville/sixty-Special Buick Roadmaster VIII

Adjustments ~206 words
  1. Before adjusting maximum Idle Speed Control (ISC) extension, check minimum idle and Throttle Position (TP) sensor adjustment. See MINIMUM IDLE under «IDLE SPEED»(ref-19418-S29919818412001010200000) . See «THROTTLE POSITION (TP) SENSOR»(ref-19418-S31535330762001010200000) .
  2. With ignition on and engine off, select ISC MOTOR override E.5.3. See appropriate G - TESTS W/ CODES article in this section. Fully extend ISC motor by pressing WARMER button on Electronic Climate Control (ECC) panel. Fuel data center should alternately display E.5.3 and 99, indicating override function has started.
  3. ISC should extend to maximum extend position. With ISC at maximum extended position, TP sensor voltage should be 1.15-1.20 volts. If TP sensor voltage is not 1.15-1.20 volts, adjust ISC plunger clockwise or counterclockwise until TP sensor parameter reads 1.18 volts.
  4. Recheck maximum extend setting. Press COOLER button to retract ISC plunger. Wait 5 seconds. Press WARMER button, and check TP sensor voltage. Readjust ISC plunger if necessary.
  5. While still in diagnostic mode, turn ignition off. Allow about 20 seconds for ISC to retract and perform a TPS LEARN routine. Re-enter diagnostic mode, and turn ignition off. A successful TPS LEARN will take 2 cycles to occur. Remove alternator disable ground wire. Start engine, and check for proper ISC motor operation.

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