TROUBLESHOOTING GUIDE — 12. LOW IDLE SPEED — WHEN A/C, P/S, OR E/L ON
F-38flowchartApplicable when A/C, P/S or E/L is ON
12. LOW IDLE SPEED — WHEN A/C, P/S, OR E/L ON
Description
DESCRIPTION
ItemsEngine speed decreases at idle when A/C, P/S, or E/L ON. A/C, P/S, headlights, blower fan and electric cooling fan operate normally
NOTE
[TROUBLESHOOTING HINTS]
1) Idle speed control malfunction
- Engine speed feedback control malfunction
- ISC valve stuck
Troubleshooting Guide (Steps 1-4)
1
Check if '00' is displayed on Self-Diagnosis Checker with ignition switch ON (page F-78)
No
Malfunction Code No. displayed: Check for cause (Refer to specified check sequence) (page F-80)
No
'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)
'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)
Yes
2
Go to next step
3
Check switches for correct operation with Self-Diagnosis Checker Monitor Lamp and ignition switch ON (page F-89)
No
Lamp not ON/OFF with specified switch: Check for cause (Refer to specified check sequence) (page F-90)
No
Lamp always ON: Check wiring between ECU terminal 1D and Self-Diagnosis Checker (page F-7)
Yes
4
Go to next step
5
Check if continuity exists between diagnosis connector terminal TEN and ground
Yes
Check for short circuit in wiring between diagnosis connector terminal TEN and ground (page F-7)
No
6
Go to next step
7
Disconnect ISC valve connector at idle and check if 'clicking' is heard from ISC valve
No
Replace ISC valve (page F-99)
Yes
8
Try known good ECU (page F-127)