Code No.02 Ne-Signal; Code No.03 G-Signal - Mazda MX-5 1990 Workshop Manual

F
SELF-DIAGNOSIS FUNCTION
CODE NO.02 Ne-SIGNAL
STEP INSPECTION ACTION
1
Are there any poor connections in crank angle sensor Yes Repair or replace connector
circuit?
No Go to next step
2 Is Code No.03 present at same time? Yes Go to next step
No Go to Step 5
3 Is there continuity between crank angle sensor terminal- Yes Go to next step
wire (B/LG) and ground?
No Check for open circuit in wiring from crank agnle
sensor to ground
4 Is there battery voltage at crank angle sensor terminal- Yes Go to next step
wire (W/R)?
No Check for open circuit in wiring from crank angle
sensor to main relay
5 Is there continuity between crank angle sensor and Yes Go to next step
ECU?
I
Crank angle sensor
I
ECU
I
No Check for open circuit in wiring from crank angle
C (W) 2E
sensor to ECU
6 Is there approx. 5V at ECU terminal 2E? (With crank an- Yes Go to next step
gle sensor connector disconnected)
No Replace ECU (Refer to page F-127)
7 Is there approx. 5V at crank angle sensor terminal-wire Yes Replace crank angle sensor
(W)? (At harness-side connector with connector discon- (Refer to page F-134)
nected)
No
Check for short circuit in wiring from crank angle
sensor to ECU
05UOFX·078
CODE NO.03 G-SIGNAL
STEP INSPECTION
ACTION
1
Are there any poor connections in crank angle sensor Yes Repair or replace connector
circuit?
No Go to next step
2 Is Code No.02 also present?
Yes Go to next step
No
Go to Step 5
3
Is there continuity between crank angle sensor terminal- Yes Go to next step
wire (B/LG) and ground?
No
Check for open circuit in wiring from crank angle
sensor to ground
4
Is there battery voltage at crank angle sensor terminal- Yes Go to next step
wire (W/R)?
No
Check for open circuit in wiring from crank angle
sensor to main relay
5 Is there continuity between crank angle sensor and Yes Go to next step
ECU?
I I
Crank angle sensor
I
ECU
No Check for open circuit in wiring from crank angle
o
(Y/L) 2G
sensor to ECU
6 Is there approx. 5V at ECU terminal 2E? (With crank an- Yes Go to next step
gle sensor connector disconnected)
No
Replace ECU (Refer to page F-127)
7
Is there approx. 5V at crank angle sensor terminal-wire
Yes Replace crank angle sensor
(Y/L)? (At harness-side connector with connector discon-
(Refer to page F-134)
nected)
No Check for short circuit in wiring from crank angle
sensor to ECU
05UOFX-079
F-82