Honda Acura NSX 1991 Service Manual page 238

PGM-FI Control System
Self-diagnosis Check Engine light indicates code 23: A problem in the circuit of the Front Knock
I
Self-diagnosis Check Engine light indicates code 53: A problem in the circuit of the Rear Knock
reported on.
jumped (page 11-18). CODE
23 and/or 53 are indicated.
Do the ECU Reset Procedures
(page 1 I-19).
Warm up the engine to normal
operating temperature (cooling
fan comes on.)
Is Check Engine light on and
(
does it indicate CODE 23 or
Turn the ignition swatch OFF.
Connect the ECU test harness to
the engine wire harness only, not
to the ECU (page 11-21).
t h e , k n o c k s e n s o r 1
connector from the engine wire
I
Check for continuity between D4
Does continuity exist?
NO
(To page 1 l-63)
I I - 6 2
, ,
0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0
b o d y
Repair short in WHT or
ECU (D4 or D3*) and
the knock sensor.
FRONT KNOCK
SENSOR
,
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
REAR
KNOCK SENSOR
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0