relay MAZDA PROTEGE 1992 User Guide

EGI EC-AT eENGINE CONTROL SYSTEM &i EC-AT CONTROL SYSTEM(2/3)
DISTRI8UTOR -W/R IEM) ::
MAIN RELAY [FUEL INJI
(SECTION B-2d
I-4)
F-2)
@
t-01 ENGINE CONTROL UNIT (EM) 82-09 DISTRIBUTOR (EM)
X L/O x G/O
!-17 INJECTOR N0,4(INJ) 82-18 WATER THERMOS:NSyFB2-25 SOLENOID VALVE
(vIcs) (INJ)

F OUTLINE
A comparison of the new and previous models is as follows.
Engine Control Unit Terminal Relation Ship Chart
Connected to
Headlight switch Terminal
Connected to Terminal
New Previous New Previou
1H IU
Water thermosensor 2E 2Q
Diagnosis connector
(TEN terminal) / II 1 IK 1 1 Throttle sensor
Rear window defroster switch
I I 21 2K
Ground (California)
Main relay (Canada)
A/C relay
Vehicle speed sensor
P/S pressure switch
A/C switch
Blower control switch 1K 2H
IL 1J
1M --
1N 1P
10 IQ
1P 1s Distributor
(G-signal) [DOHC]
Intake air thermosensor
Solenoid valve
(Purge control)
Ground (Injector)
Ground (Output)
Ground (CPU) 2J 2G
2K 2P
20 2x
___
Stoplight switch 1Q 10
Ground (Input)
1 I I 1 ! 3D ! 2D
Cruise control main switch
1 lS / - II8cRalnardega,y
Throttle sensor
(Idle switch)
Distributor
(Ne-signal) 1T 1N
2A 2E
2B 20
2C 2N Solenoid valve
(VICS)
--.-- I_-
Solenoid valve
(Pressure regulator) [BP] 31 2s
-- -_
3M 2T
Airflow meter
Oxygen sensor
-
Fan switch 1 2D 1 IR 1 1 lniector (Nos. 2, 4) I 3v I 2v
23UOFX-01 I
F-l 4

F OUTLINE
COMPONENT DESCRIPTIONS
Component
Air cleaner
Airflow meter
Mr valve
Atmospheric pressure
Sensor
Catalytic converter Function Remark
Filters air entering throttle body
Detects amount of intake air; sends signal to intake air thermosensor and fuel pump
ECU switch included
Supplies bypass air into dynamic chamber
l Engine speed increased to shorten
when engine is cold warm-up period
l Thermowax type l Installed in dynamic chamber
Detects atmospheric pressure; sends signal Built in ECU
to ECU
Reduces HC, CO, and NOx by chemical Monolith type
reaction Charcoal canister
Stores fuel tank fumes while engine stopped Check valve
Controls pressure in fuel tank Two-way type Circuit opening relay
Voltage for fuel pump while engine running Clutch switch (MTX)
Detects clutch condition; sends signal to Switch OFF when clutch pedal released
ECU Diagnosis connector
Concentrated service connector 25pin (located near left suspension mount-
Concentrated terminals: ing block)
1. EGI self-diagnostic terminal
2. EC-AT self-diagnostic terminal
3. Test terminal
4. Fuel pump check terminal
5. Cooling fan check terminal
6. Engine rpm output terminal Dynamic chamber
Interconnects all cylinders Engine control unit (ECU) Detects the following:
1. A/C operation 1. A/C switch
2. Air/fuel ratio (Oxygen concentration) 2. Oxygen sensor
3. ATF thermosensor
4. Atmospheric pressure 4. Atmospheric pressure sensor
5. Braking signal 5. Stoplight switch (MTX)
6. Cranking signal 6. Ignition switch (START Position)
7. DRL (Daytime Running Light) operation 7. DRL relay (Canada)
8. E/L operation 8. Blower motor switch, cooling fan relay,
headlight switch, and rear window
defroster switch
9. Engine coolant temperature 9. Water thermosensor
10. Engine speed 10. Distributor (Ne-signal)
11. Ignition ON signal 11. Ignition switch
12. In-gear condition 12. Neutral and clutch switches (MTX)
13. Inhibitor switch (ATX) 13. N range, D range, S range, L range
switch
14. Intake air amount 14. Airflow meter
15. Intake air temperature 15. Intake air thermosensor
(In airflow meter)
16. No.1 piston TDC of compression
17. P/S operation
18. Shift solenoid (ATX)
19. Test signal (Ignition timing, idle speed,
Malfunction code No.)
20. Throttle valve fully closed/fully open
condition 16. Distributor (G-signal) DOHC)
17. P/S pressure switch
18. 1-2, 2-3, 3-4, Lockup solenoid
19. Diagnosis connector
(TEN terminal)
20. Throttle sensor (MTX)
21. Throttle valve opening angle
22. Turbine sensor 21. Throttle sensor (ATX) .__r
F-10

OUTLINE
Component Function Remark
Engine control unit (ECU) Controls operation of the following:
(Cont’d)
1. A/C (Cut-off) 1. A/C relay
2. Fail-safe function 2. Self-Diagnosis Checker and MIL
3. Fuel injection system 3. Injector
4. idle speed control 4. Idle speed control (ISC) valve
5. Ignition timing control system 5. Igniter
6. Monitor function 6. Monitor lamp (Self-Diagnosis Checker)
7. Pressure regulator control system 7. Solenoid valve
(Pressure regulator control) (BP)
8. Purge control system 8. Purge control solenoid valve
9. VICS 9. Solenoid valve (WCS) (DOHC) Fuel filter
Filters particles from fuel Fuel pump
Provides fuel to injectors l Operates while engine running l Installed in fuel tank Igniter
Receives spark signal from ECU and gener-
ates high voltage in ignition coil Ignition switch
Engine cranking signal sent to ECU (START position)
Inhibitor switch (ATX)
Detects in-gear condition; sends signal to Switch ON in N or P range
ECU Injector
Intake air thermosensor
Idle speed control (ISC)
valve
Main relay
(FUEL INJ relay)
MIL (Malfunction
indicator lamp)
Neutral switch (MTX)
Oxygen sensor
PCV valve
P/S pressure switch
Pressure regulator
Resonance chamber
Resonance duct
Separator
Stoplight switch
Solenoid valve
(Purge control)
Shutter valve actuator
(DOHC)
Throttle body
Throttle sensor
Injects fuel into intake port l Controlled by signals from ECU
l High-ohmic injector
Detects intake air temperature; sends signal Installed on dynamic chamber
to ECU
Controls bypass air amount Controlled by duty signal from ECU
Supplies electric current to injectors, ECU,
etc.
Lamp flashes to indicate malfunction code
number of input and output devices
Detects in-gear condition; sends signal to
ECU
Detects oxygen concentration; sends signal
to ECU
Controls blowby gas introduced into engine
Detects P/S operation; sends signal to ECU
Adjusts fuel pressure supplied to injectors
Reduces intake air noise
Reduces intake air noise
Prevents fuel from flowing into charcoal
canister
Detects braking operation (deceleration),
sends signal to ECU
Controls evaporative fumes from canister to
intake manifold
Closes/opens shutter valve to improve
torque characteristics
Controls intake air quantity
l Detects throttle valve fully closed/fully
opened condition (MTX) TEN terminal grounded
Switch ON in neutral
Zirconia ceramic and platinum coating
P/S: ON when steering wheel turned right or
left
Controlled by duty signal from ECU
For Variable inertia charging system (VICS*)
Integrated throttle sensor, dashpot, and ISC
valve
l Detects throttle valve opening angle
(A-W
l Sends signals to ECU
F-l 7

F TROUBLESHOOTING GUIDE
Output Devices and Engine Conditions
Note
. The data in this chart is for reference only.
INJECTOR
CONDITIONS
CRANKING
-COLD ENGINE
l COLD AIR l COLD COOLANT
COLD START
-FAST IDLE
l COLD AIR l COLD COOLANT
COLD DRIVEAWAY
-PART THROTTLE
l COLD AIR l COLD COOLANT
WARM DRIVEAWAY
-PART THROTTLE
. WARM AIR
l WARM COOLANT
HOT CRUISE
l WARM AIR l WARM COOLANT Zero
One
mrnute
Two
minutes
Three
minutes
I AIR
INJECTION “AL”E
INJECTION TlMlNG
A
All A
cylinders
each
ignition
pulse
1
Rich Open:
coolant
tem-
perature:
Below
40%
(104OF)
,
I/
Rich and
2-group” 1’
lean l-group” /I
,
i
HOT ACCELERATION
-60% THROTTLE
-lOT ACCELERATION
-WIDE OPEN
THROTTLE
Closed ISC
VALVE
1, THREE-WAY
SOLENOID SOLENOID
VALVE VALVE
(PURGE
(PRESSURE
CONTROL) REGULATOR
CONTROL)‘3
c
OFF
(Purge
cut)
Large
1
, AK
RELAY
amount or
bypass air
OFF
(Vacuum
to
pressure
regulator)
After start-
rng: ON dur-
ing hot start
only (Vacu-
um cut)
OFF
l 2 SOHC, *’ BP
F-22

F TROUBLESHOOTING GUIDE
SYMPTOM TROUBLESHOOTING
2 CRANKS NORMALLY BUT WILL NOT START (NO COMBUSTION)
l Engine cranks at normal speed but shows no sign of “firing”
DESCRIP-
*Battery in normal condition
TION
*Throttle valve not held fully open while cranking (Dechoke system not operate)
*Fuel in tank [TROUBLESHOOTING HINTS]
Because of no combustion, possibly no fuel is injected to engine or no ignition at all cylinders
:I) No spark
@I Low fuel line pressure
l Ignition control malfunction
@ Low engine compression l Ignition system component malfunction
3 No fuel injection
l Fuel pump inoperative l Injectors inoperative
TEP INSPECTION
ACTION
1 Check if strong blue spark is visible at discon-
Yes Go to Step 3
netted high-tension lead
No Go to Step 2
2 Check if “00” is displayed on Self-Diagnosis
Yes Check ignition system (Refer to
Checker with ignition switch ON
Troubleshooting “Misfire”) w page G-5
w page F-82
No Service Code No. displayed
Check for cause (Refer to specified
check sequence) w page F-83
“88” flashes
Check ECU terminal 1F voltage w page F-150
Specification: Battery voltage
(Ignition switch ON)
W: SELF TEST e If OK, replace ECU w page F-149 c3 If not OK, check wiring between
SELECT SW: A ECU and Self-Diagnosis Checker
3 Connect diagnosis connector terminals F/P and
Yes Check if engine starts in this condition
GND with jumper wire and check for fuel pump
operating sound with ignition switch ON c3 If starts, check circuit opening relay c7 page F-129
w page F-125
c3 If does not start, go to Step 5
DIAGNOSIS C
Go to next step ._-,
._. ,
F-30

F TROUBLESHOOTING GUIDE
15
ENGINE STALLS ON DECELERATION
DESCRIP-
l Engine unexpectedly stops running while decelerating or after deceleration
TION l Idle condition normal
[TROUBLESHOOTING HINTS]
Engine speed drops too much when releasing accelerator or poor connector connection disconnected by deceleration
force
3 Idle speed control malfunction
3 Fuel cut control malfunction @ Idle speed misadjustment
TEP INSPECTION
ACTION
1
Check if idle condition is normal Yes
Go to next step
No Adjust or perform troubleshooting
Nos. 8-11 “ROUGH IDLE” v page F-42
F-48
--
2
Check if “00” is displayed on Self-Diagnosis Yes Go to next step
Checker with ignition switch ON
W page F-82 No
SYSTEM SELECT: 1 Service Code No. displayed
Check for cause (Refer to specified
check sequence) w page F-83
“88” flashes
Check ECU terminal IF voltage LIT= page F-150
Specification: Battery voltage
(Ignition switch ON)
W: SELF TEST + If OK, replace ECU w page F-149
Q If not OK, check wiring between
ECU and Self-Diagnosis Checker
3 Check switches for correct operation with Self-
Yes Go to next step
Diagnosis Checker Monitor Lamp with ignition
switch ON
w page F-105 No
Lamp not ON or OFF with specified
switch
Check for cause (Refer to specified
check sequence) CT page F-106
-,-y/
,’ Lamp always ON
Check wiring between ECU terminal 1 D
and Self-Diagnosis Checker
W: SELF
TEST
4 Check if ECU terminal voltages are OK
Yes Go to next step
MTX...Especially IV, 2D, 20, 2U, 2V and 2Q
ATX... Especially 28, 2E, 30, 3U, and 3V
w page F-150 No Check for cause w page F-151
5
Check for poor connection of following parts
Yes Repair or replace
. Ignition coil
l Igniter l Distributor
-- l High-tension lead
No l Injector Go to next step l Circuit opening relay l ECU
F-54

TROUBLESHOOTING GUIDE
16 ENGINE STALLS SUDDENLY (INTERMITTENT)
DESCRIP- l Engine intermittently stops running
TION l Before stalling, engine condition OK [TROUBLESHOOTING HINTS]
@ Intermittently no spark or no-fuel injection caused by ve-
hicle vibration, acceleration, or deceleration
*Poor connection in wire harness
3 INSPECTION
Check if “00” is displayed on Self-Diagnosis
Checker with ignition switch ON c7 page F-82
g
-%ELECT SW: A
Check for poor connection of following parts l ignition coil
l igniter l Distributor l High-tension lead l lniector
l Ci;cuit opening relay l ECU
Check if ECU terminal voltages are OK
MTX...Especially lB, 2A, 28 and 2C
ATX... Especially lB, 3A, 38 and 3C w page F-150
Note
l When checking voltages, tap, move, and
wiggle harness and connector to recreate
problem
Yes
No Service Code No. displayed
Check for cause (Refer to specified
check sequence) Note
l When checking wiring harness and
connectors, tap, move, and wiggle
suspect sensor and/or harness to
recreate problem
“88” flashes
Check ECU terminal IF voltage w page F-150
Specification: Battery voltage
(Ignition switch ON)
c3 If OK, replace ECU CT= page F-149
+ If not OK, check wiring between
ECU and Self-Diagnosis Checker
Yes
Repair or replace
No Go to next step
Yes
No
T ACTION
Go to next step w page F-83
Go to Troubleshooting No.2
‘CRANKS NORMALLY BUT WILL NOT
START (NO COMBUSTION)” CT- page F-30
Check for cause D page F-151
F-56

TROUBLESHOOTING GUIDE
27 MIL ALWAYS ON
DESCRIP- *Self-Diagnosis Checker does not indicate Malfunction Code No. but MIL always ON
TION
[TROUBLESHOOTING HINTS]
*Short circuit in wiring harness
l ECU malfunction
iTEF 1
1
-
s
Disconnect (Y/B) wire from ECU and check if
MIL goes off
‘YIB
ATX YIB
INSPECTION ACTION
Yes Replace ECU CT page F-149
No Check for short circuit in wiring be-
tween instrument cluster and ECU
23UOFX-042
28
MIL NEVER ON
IESCRIP- *Self-Diagnosis Checker indicates Malfunction Code No. of input device but MIL never ON
RON *Other indicator and warning lamps OK
:TROUBLESHOOTING HINTS]
b Bulb burned
‘Open circuit in wiring harness
m ECU malfunction
TEP INSPECTION
ACTION
1 Ground (Y/B) wire at ECU with jumper wire and
Yes Check connection of ECU connector
check if MIL comes on
MTX e If OK, replace ECU w page F-149
I- i -!~ !r--~r’:~;-‘;- --~_:- ,
1 i r 1 1 1 ;-.:,~;~$~& {-;&# ,$&]j 4 If not OK, repair ECU connector
! No
Check if bulb is OK
ATX 13 If OK, repair (Y/B) wire between
ECU and instrument cluster
e If not OK, replace bulb CT page T-83
23UOFX-043
29 A/C DOES NOT WORK
DESCRIP- *Blower fan operates but magnet clutch does not operate
TION
[TROUBLESHOOTING HINTS]
*Open or short circuit in wiring harness
*A/C relay, A/C switch, or magnetic clutch malfunction
l ECU malfunction
TEP/ INSPECTION ACTION
1 1 Check ECU
terminal 10 (MTX) 10 (ATX) voltage 1
Yes Check ECU terminal 1 J (MTX) 1 L (ATX)
OK
CT= page F-152
MTX
T7J++!;i”-
L
ATX
No voltage OK
CT page F-152
1-3 If OK, check A/C system
c3- page U-30
~3 If not OK, replace ECU CT page F-149
Check for cause w page F-153
F-77

SELF-DIAGNOSIS FUNCTION F
PREPARATION
SST
49 6019 9AO
System Selector For
diagnosis 49 HO18 9Al
Self-Diagnosis
Checker For
diagnosis
SERVICE CODE NUMBER
Inspection Procedure
1. Connect the SST to the diagnosis connector.
2. Set switch @to position 1.
3. Set TEST SW to SELF-TEST position.
23UOFX-048
03UOFX.059
I
4. Connect the SST to the System Selector and a ground
5. Set the select switch to position A.
6. Turn the ignition switch to ON.
7. Verify that 88 flashes on the digital display and the buzzer
sounds for 3 sec. after turning the ignition switch ON.
8. If 88 does not flash, check the main relay (FUEL INJ relay)
(Refer to page F-172) power supply circuit, and diagno-
sis connector wiring.
9. If 88 flashes and the buzzer sounds continuously for more
than 20 sec., check for a short circuit between the engine
control unit terminal 1 F and the diagnosis connector. Re-
place the engine control unit if necessary and perform Steps
3 and 7 again.
23UOFX-049 IO. Note any code numbers and check for the causes by refer-
ring to the check sequences shown on pages F-88
through F-103. Repair as necessary.
Note
l Cancel the code numbers by performing the after-
repair procedure following repairs.
(Refer to page F-104.)
I 23UOFX-050
F--83