TROUBLESHOOTING GUIDE — 20 ENGINE STALLS AT IDLE — WHEN A/C, P/S, OR E/L ON
F-50prose procedure20 ENGINE STALLS AT IDLE — WHEN A/C, P/S, OR E/L ON
DESCRIPTION:
- Engine unexpectedly stops running at idle when A/C, P/S, or E/L ON
- A/C, P/S, headlight, blower fan and electric cooling fan OK
NOTE
[TROUBLESHOOTING HINTS]
① Idle speed control malfunction
• No input signal from switch
• Idle speed misadjustment
• ISC valve stuck
Troubleshooting Guide (steps 1–6)
1
INSPECTIONCheck if "00" is displayed on Self-Diagnosis Checker with ignition switch ON (page F-78)
RESULTYes
ACTIONGo to next step
1
INSPECTIONCheck if "00" is displayed on Self-Diagnosis Checker with ignition switch ON (page F-78)
RESULTNo
ACTIONMalfunction Code No. displayed
Check for cause (Refer to specified check sequence) (page F-80)
"88" flashes
Check ECU terminal 1F voltage (page F-128)
Voltage: Approx. 12V (Ignition switch ON)
- If OK, replace ECU (page F-127)
- If not OK, check wiring between ECU and Self-Diagnosis Checker (page F-7)
2
INSPECTIONCheck switches for correct operation with Self-Diagnosis Checker Monitor Lamp and ignition switch ON (page F-89)
RESULTYes
ACTIONGo to next step
2
INSPECTIONCheck switches for correct operation with Self-Diagnosis Checker Monitor Lamp and ignition switch ON (page F-89)
RESULTNo
ACTIONLamp not ON/OFF with specified switch
Check for cause (Refer to specified check sequence) (page F-89)
Lamp always ON
Check wiring between ECU terminal 1D and Self-Diagnosis Checker (page F-7)
3
INSPECTIONCheck if ECU terminal voltages are OK (1G, 1P, 1U, 2D, 2Q and 2W) (page F-128)
RESULTYes
ACTIONGo to next step
3
INSPECTIONCheck if ECU terminal voltages are OK (1G, 1P, 1U, 2D, 2Q and 2W) (page F-128)
RESULTNo
ACTIONCheck for cause (Refer to "Check Point for Each Terminal") (page F-131)
4
INSPECTIONCheck for correct idle speed (page F-76)
Idle speed: 850 ± 50 rpm
RESULTYes
ACTIONGo to next step
4
INSPECTIONCheck for correct idle speed (page F-76)
Idle speed: 850 ± 50 rpm
RESULTNo
ACTIONAdjust (page F-76)
5
INSPECTIONDisconnect ISC valve connector at idle and check if "clicking" is heard from ISC valve
RESULTYes
ACTIONGo to next step
5
INSPECTIONDisconnect ISC valve connector at idle and check if "clicking" is heard from ISC valve
RESULTNo
ACTIONReplace ISC valve (page F-99)
6
INSPECTIONTry known good ECU and check if condition improves (page F-127)
RESULT
ACTION
See also
F-78SELF-DIAGNOSIS FUNCTIONF-80SELF-DIAGNOSIS FUNCTIONF-128CONTROL SYSTEM - Engine Control Unit Terminal Voltage TableF-127CONTROL SYSTEM - Engine Control Unit InspectionF-7OUTLINE - WIRING DIAGRAMF-89SELF-DIAGNOSIS FUNCTIONF-131CONTROL SYSTEM - Check Point for Each TerminalF-76ENGINE TUNE-UPF-99IDLE SPEED CONTROL (ISC) SYSTEM