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DTC P1596-A: Speed Control Switch Always High

NOTE: For connector terminal ID, see CONNECTOR IDENTIFICATION . For wiring diagram, see WIRING DIAGRAMS article.
  1. Using scan tool, access speed control inputs. While observing scan tool, push speed control ON/OFF switch several times, then leave on. If scan tool showed speed control inputs switching on and off, go to DTC P1596-B: SPEED CONTROL SWITCH ALWAYS HIGH . If scan tool does not show speed control inputs switching on and off, go to next step.
  2. Disconnect speed control ON/OFF switch 2-pin connector. Using a DVOM, check voltage of speed control switch signal circuit at speed control ON/OFF switch 2-pin connector. If voltage is 6 volts or less, go to next step. If voltage is more than 6 volts, repair short to voltage on speed control switch signal circuit. Perform TEST VER-4A: SPEED CONTROL VERIFICATION .
  3. Turn ignition off. Using a DVOM, check resistance of speed control switch ground circuit at speed control switch 2-pin connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open ground circuit to speed control switch. Perform TEST VER-4A: SPEED CONTROL VERIFICATION .
  4. Disconnect Powertrain Control Module (PCM) connector. Using a DVOM, check resistance of speed control switch signal circuit between speed control ON/OFF switch 2-pin connector and PCM connector terminal No. 41. See SPEED CONTROL SWITCH 2-PIN CONNECTOR WIRE IDENTIFICATION  table and PCM CONNECTOR WIRE IDENTIFICATION  table. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, go to step  6.
  5. Using a DVOM, check resistance between speed control switch 2-pin connector terminals identified in SPEED CONTROL SWITCH RESISTANCE  table. If resistance is within specification, replace PCM. Perform TEST VER-4A: SPEED CONTROL VERIFICATION . If resistance is not within specification, replace on/off switch. Perform TEST VER-4A: SPEED CONTROL VERIFICATION .
  6. Disconnect clock spring 5-pin connector. Using a DVOM, check resistance of speed control switch signal circuit between clock spring connector and PCM connector terminal No. 41. See CLOCK SPRING 5-PIN CONNECTOR WIRE IDENTIFICATION  table and PCM CONNECTOR WIRE IDENTIFICATION  table. If resistance is less than 5 ohms, replace clock spring. Perform TEST VER-4A: SPEED CONTROL VERIFICATION . If resistance is 5 ohms or more, repair open speed control switch signal circuit between clock spring connector and PCM connector. Perform TEST VER-4A: SPEED CONTROL VERIFICATION .
SPEED CONTROL SWITCH 2-PIN CONNECTOR WIRE IDENTIFICATION

Application Wire Color
Speed Control Switch Ground Circuit Black/Light Green
Speed Control Switch Signal Circuit Red/Light Green
PCM CONNECTOR WIRE IDENTIFICATION

Application Wire Color
PCM Terminal No. 41
Speed Control Switch Signal Circuit Red/Light Green
SPEED CONTROL SWITCH RESISTANCE

Switch Position Ohms
CANCEL 900-918
SET 6584-6716
ACCEL/RESUME 15246-15554
ON/OFF Zero (Continuity)
COAST 2911-2969
CLOCK SPRING 5-PIN CONNECTOR WIRE IDENTIFICATION

Application Wire Color
Speed Control Switch Signal Circuit Red/Light Green
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