Pcm Power Relay (Battery Power); Eec Pwr Fuse (Pcm Memory Power); Ground - Mazda B-Series 1997 Workshop Manual

CONTROL SYSTEM (FOR 2 . 3 ~ I 3 . 0 ~ 1 4 . 0 ~ )
FT
PCM POWER RELAY (BATTERY POWER)
If the circuit is open, the engine will not start.
If the circuit is shorted, the
EEC PWR
fuse (30A) will burn out.
t
Condition
Circuit
Inspection
1. Measure resistance between pins 85 and 86 of the relay.
Specification: 40-1 20 ohms.
Engine will not start
PCM (97)-PCM power relay
Poor ground O ~ e n circuit
EEC PWR fuse (30A)
burns out with ignition
switch ON
4. If not as specified, replace the PCM power relay.
Short circuit
86
-
- &
J
2. Measure resistance between pin 85 and both pins 30 and
87 of relay.
Specification: greater than 10,000 ohms.
COIL
- 85
AND 86
COMMON
-
30
3. Apply battery voltage (B+) and check for continuity
NO
-
87
between terminals of the relay.
NC
-
8 7 ~
Specification:
B+ : Battery positive voltage
EEC PWR FUSE (PCM MEMORY POWER)
If the EEC PWR fuse circuit has an open or short, Diagnostic Trouble Code No. F'0603, PI605
is output.
If the circuit is open, the PCM rnemory function will not operate and Diagnostic Trouble Codes
for intermittent malfunctions will not be indicated. Also,the learning control will be canceled.
If the circuit is shorted, the EEC PWR fuse (30A) will burn out.
'1 044-6 6BUOFT-244
Circuit
-
-
Condition
open circuit
T--
- P o c G n d m d - - - - I
Terminal 85-86
B+ applied
- - - -
-
-
PCM (55)-Maln fuse block
,
Code No. PO603 or
I
-
burns out. Code No. NIA
P I 605 ouout
Terminal 30-87
GROUND
If there is a poor ground, the engine may not start.
rp
Circuit
PCM (24)-Ground
PCM (25)-Ground
PCM (76)-Ground
Engine may not start
fl
Engine will not start
1
NA
1
Hard starting
1
PCM (77)-Ground
PCM (1 03)-Ground
6BUOFT-246
Condition
i Open circuit Short circuit