Toyota 4-Runner 1985 Repair Manual page 193

I-24
EFI SYSTEM - Diagnosis System
EFI15A
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F11171
CANCELLING OUT DIAGNOSTIC CODE
1 . A fter repair of the trouble area, the diagnostic code retained
in memory by the ECU must be cancelled out by removing
the fuse EFI (15A) for 30 seconds or more, depending on
ambient temperature (the lower the temperature, the
longer the fuse must be left out) with the ignition switch
off.
NOTE:
• Cancellation can also be done by removing the battery
negative ( - ) terminal, but in this case other memory
systems (radio ETR, etc.)will also be cancelled out.
• If the diagnostic code is not cancelled out, it will be re-
tained by the ECU and appear along with a new code in
event of future trouble.
• If it is necessary to work on engine components requir-
ing removal of the battery terminal, a check must first
be made to see if a diagnostic code has been recorded.
2. After cancellation, road test the vehicle, if necessary, con-
firm that a "normal" code (No.1) is now read on the
"CHECK ENGINE" warning light.
If the same diagnostic code is still indicated, it indicates
that the trouble area has not been repaired thoroughly.
DIAGNOSIS INDICATION
(1) I ncluding "normal", the ECU is programmed with the fol-
lowing 13 (22R-E), 14 (22R-TE) diagnostic codes.
(2) When 2 or more codes are indicated, the lowest number
(code) will appear first.
(3) All detected diagnostic codes, except 11 and 13, will be
retained in memory be the ECU from the time of detection
until cancelled out.
(4) Once the malfunction is cleared, the IICH ECK ENG I NE"
warning light on the instrument panel will go out but the
diagnostic code(s) remain stored in ECU memory (except
for code 11 and 13).
A03887