Test TC-86A - Speed Control Switch Always High
NOTE:
For connector terminal ID, see CONNECTOR IDENTIFICATION DIRECTORY . For wiring diagram, see WIRING DIAGRAMS - NON-TURBO
article.
- Using scan tool, read speed control inputs. While observing scan tool display, push speed control ON/OFF switch several times and leave on. If scan tool displays speed control switch on and off, go to TEST TC-86B. If scan tool does not display speed control switch on and off, go to next step.
- Disconnect 2-pin speed control ON/OFF switch connector (located behind speed control ON/OFF switch). Using scan tool in voltmeter mode, check voltage on 2-pin speed control switch connector signal circuit Red/Light Green wire. If voltage is 4.8 volts or less, go to next step. If voltage is more than 4.8 volts, repair short to voltage on signal circuit. Perform TEST VER-4A.
- Turn ignition off. Using scan tool in ohmmeter mode, check resistance of 2-pin speed control switch connector ground circuit Black/Light Green wire. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open ground circuit. Perform TEST VER-4A.
- Disconnect Powertrain Control Module (PCM) connector. Using scan tool in ohmmeter mode, check resistance of signal circuit Red/Light Green wire between 2-pin speed control switch connector and PCM connector terminal No. 41. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, go to step 6).
- Using an external ohmmeter, check resistance across speed control ON/OFF switch terminals. If resistance is less than 25 k/ohms, replace PCM. Perform TEST VER-4A. If resistance is 25 k/ohms or less, replace speed control ON/OFF switch. Perform TEST VER-4A.
- Disconnect 4-pin clockspring connector. Using an external ohmmeter, check resistance of speed control ON/OFF switch signal circuit Red/Light Green wire between 4-pin clockspring connector and PCM connector terminal No. 41. If resistance is less than 5 ohms, repair open signal circuit at clockspring connector. Perform TEST VER-4A. If resistance is 5 ohms or more, repair open signal circuit between 4-pin clockspring connector and PCM connector terminal No. 41. Perform TEST VER-4A.