1990 MITSUBISHI SPYDER check engine

ENGINE
Scan tool 92
C o d e G e n e r a l s c a n t o o l L o w S p e e d F a n
No.Circuit, 35,
[Comment]l Relay coil open or shortedBackgroundlThe low speed radiator fan relay controls the low of the radiator fan. l
Ignition switch output circuit openOne side of the relay control coil is supplied with 12 volts when the ignition switch isl
Low speed radiator fan l o r turned to the ON position.
l The circuit is completed when the other side of the relay coil is grounded by the PCM.l .
lThe PCM grounds the relay control circuit depending
on engine coolant temperature etc. . . Range of Checkl
Battery voltage: 10 or morel Ignition switch: ONSet ConditionlAn open or short-circuit condition is detected in t he low speed radiator fan relay controlcircuit for 3 seconds.
NGMeasure at the PCM connector Check the radiator fan relay drcuit.lDisconnect the connector, and measure at the harnes s side.
l Voltage between 55 and ground
(ignition switch: ON)
OK: Battery positive voltage
l Connect a jumper wire between 55 and ground.
(Ignition switch: ON)
OKRadiator fan runs at low speed.
OKNG Repair
OK
Check trouble symptom.
Replace the PCM.
NG
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ENGINE
Scan tool 93
Code General scan tool High Speed Fan
No.Control Relay Circuit
35
[Comment]
Background
lThe high speed condenser fan relay controls the hig h speed operation of the condenserfan.lOne side of the relay control coil is supplied with 12 volts when the ignition switch is
turned to the ON position.
lThe circuit is completed when the other side of the relay coil is grounded by the PCM.lThe PCM grounds the relay control circuit depending on engine coolant temperature and
other conditions.
Range of Check
l Battery voltage:
or more Ignition switch: ONSet ConditionAn open or shorted condition is detected in the hig h speed condenser fan relay controlcircuit for 3 seconds.
lRelay, coil open, shorted . ..
lHigh speed condenser fan relay control circuito p e n PCM failed
Measure at the PCM connector lDisconnect the connector, and measure at the harnes s side.Check the condenser fan circuit.
l Voltage between 19 and ground
(Ignition switch: ON)
OK: Battery positive voltage
l Connect a jumper wire between 19 and ground.
(Ignition switch: ON)
OK A/C condenser fan runs at high speed.
OK. . . . NG RepairCheck the following connector: IOK
Check trouble symptom.
Replace the PCM.
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ENGINE . .
Scan tool 96
[Comment]l The TCM outputs no messages.lCommunication line between failed..
.
l PCM failed
CHECK BY SCAN TOOL
l Can the scan tool communicate with the TCM?
, l Disconnect the PCM connector. me
l Can the scan tool communicate with the TCM?
,No
Replace PCM.
, N G C h e c k t h e f o l l o w i n g .
Measure at the data link connector. l
Disconnect the PCM connector.
l Voltage between 27 and ground (Ignition switch: ON)
O K :
l Voltage between and ground (Ignition switch: ON)
O K :
l Resistance between 27 and 28
O K :
OK
Measure at the data link connector. l Connect the PCM connector.
l Disconnect the TCM connector.
l Resistance between 27 and
O K :
OK
Check the harness wire between the PCM and the
OK.
Replace the TCM.
Replace the PCM.
Check the following connectors:
OK
NG Repair
Check trouble symptom.
N G
the PCM.I
OK
Check trouble symptom.
Replace the TCM.
N G
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ENGINE (NON-TURBO)>
Scan tool 101
Code General scan tool
No.Fuel Pump Relay Control Circuit
42
[ C o m m e n t ]l Relay open or shortedBackgroundFuel pump relay control open l The fuel pump relay control the battery voltage sup plied to the fuel pump.lThe PCM provides a ground path for the fuel pump re lay. I n o p e r a t i v e P C M ,
l This DTC indicates an open or short-circuit in the control Range of Check Battery voltage: 10 or more
l Ignition switch: ON
Set Conditionl Open or short circuit is detected in fuel pump rela y control circuit for 3 seconds.
NGCheck the fuel pump Replace
OK,
Measure at the fuel pump relay connector Check the following connectors: lDisconnect the connector, and measure at the harnes s side.
l Voltage between 6 and ground
OK: Battery positive voltage
OK
Check the harness wire between the pump connector. Repair, if necessary.
N G
Check the following connector: Repair
OK
Check trouble symptom.
NG
Check the harness wire between theconnector.
NG Repair
OK
Replace the PCM.
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ENGINE (NON-TURBO)>
Scan tool 102
Code General scan tool
No. Response
21
[Comment]
Backgroundl Heated oxygen sensor failed
l Exhaust system failed
During closed-loop operation the PCM monitors the h eated oxygen sensor response ratefor proper operation.-Pipes
lResponse rate is the time required for the heated o xygen sensor to switch from - s e a l sonce the sensor is exposed to a richer than the ide al air fuel mixture.
If the response rate is below the acceptable limit, the PCM stores a diagnostic troublel harness and connectors l
l PCM failed .code.Range of Checkl Engine coolant temperature greater than l Approximately three minutes elapsed time after star t-up.
lVehicle has operated at more than for 75 seconds with engine coolant temperatureat.
l Power steering pressure switch is offl Vehicle is at idle with engine speed between 512 an d 864 lThis test may be inhibited if the A/C is cycling to o rapidly. (Testing with the off issuggested)Set Condition.Heated oxygen sensor does not produce 0.67 volt out put and/or does not perform enoughswitches within the test threshold time of 6 seconds.
NGCheck the exhaust l Check for cracks or exhaust leaks. Repair
OK
Check the following connectors: N G Repair
OK
Check trouble symptom.
NG
NG
Check the harness wire between Repair
sensor (front).
OK
[Replace the heated oxygen sensor (front).
Revision

ENGINE (NON-TURBO)>
Scan tool 103
Code General scan tool
No.Upstream Failure
21
[Comment]
Background
l The PCM continues to monitor this system after the key is OFF.
l The PCM waits some periods to allow the heated oxyg en sensors to cool.
l Once the PCM calculates that the heated oxygen sens or is cooled, it energizes the
relay (ASD relay) and tests for the heated oxygen sensor operation.
Range of Check
5 seconds or more after turning the ignition switch to OFF. Battery positive voltage: or morelThe heated oxygen sensor output line voltage rises by 0.49 or more within 144 secondsafter turning the ignition switch to OFF. The initial rise of the output line voltage is less than 1.57 V.Set ConditionHeated oxygen sensor’s circuit does not show the ap propriate decrease of voltage the test.
l Heated oxygen sensor heater open l harness and connectors ,
Measure at the heated oxygen sensor (front) connect or l
Disconnect the connector, and measure at the harnes s side.
SCAN TOOL Actuator test
relay (ASD relay) Check the following connector: everyapprox. 1. Voltage between 4 and ground
[Measure with the relay (ASD relay) on]
OK: Battery positive voltage Check the harness wire between the and
2. Continuity between 3 and ground the heated oxygen sensor connector. if
OK: Continuity
2. NG Check the harness wire between the heated oxygen sensor and
OKthe ground. Repair, if necessary.
NGCheck the followingconnect Repair
OK
Check trouble symptom.
NG
Replace the heated oxygen sensor (front).
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ENGINE (NON-TURBO)>
Scan tool 106
Code General scan tool
No.Multiple Cylinder Mlsfire
43
[Comment]Background
l Excessive engine misfire results in increased catal yst temperature.
l Severe misfire could cause catalyst damage.
l To prevent catalytic converter damage, the PCM moni tors engine misfire.
l The PCM monitors for misfire during most engine ope rating conditions.
lWhen a misfire is detected, the PCM stores a diagnostic trouble code and causes the to either flash or illuminate continuously during active misfire.
Range of Check
l MAP voltage is less than 1.60
l Engine speed is between 2200 and 2800 l Engine coolant temperature is greater than l Vehicle speed less than Set Condition
l 1000 Rev Misfire
The PCM detects misfire in more than 1.6% of the en gine cycles in a 1000 revolution
period.l 200 Rev MisfireThe PCM detects misfire in more than 15% of the eng ine cycles in a 200 revolution period.
.
Spark plugs or wires failed
l Ignition coil failed
l Crankshaft position piston rings v a l v e s
l Head gasket failed
l C r a c k e d
l Fuel lines and filter failed
l Fuel failed
l failed
l Wiring and connectors failed
l Engine coolant
l Timing belt tooth broken,
l EGR
SCAN TOOL SENSOR READ TESTS (Data list)
05 Engine coolant temperature sensor (Refer to Check the engine coolant temperature circuit.
(Refer to INSPECTION PROCEDURE 38.)
OK
SCAN TOOL SENSOR READ TESTS (Data list)
27 Intake air temperature sensor (Refer to
OK
Check the intake air temperaturecircuit.(Refer to INSPECTION PROCEDURE
SCAN TOOL SENSOR READ TESTS (Data list)
11 MAP sensor reading (Refer to
OK
OK
Check the MAP sensor circuit.(Refer to INSPECTION PROCEDURE 40.)
SCAN TOOL SENSOR READ TESTS (Data list)
Check the following connectors: 66 Oxygen sensor volts (front) (Refer to OK: Repeat and alternately whenidling.
Check the fuel pressure. (Refer to Check the harness wire between the PCM and the cran kshaft
position sensor connector.
l Check the injectors for operation sound.
l Check the injectors for fuel leakage.
l Check the evaporative emission control system.
Check the following items.
l Check the ignition coil, spark plug cables.
l Check the compression pressure.
Check the EGR
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E N G I N E
Scan tool
Cylinder Misfire
Code General scan tool Cylinder Misfire
No.Cylinder MisfireProbable cause
Cylinder Misfire
43,
[Comment]
Backgroundl Spark plugs or ,
l Excessive engine misfire results in increased catal yst temperature.l l . valves
l Severe misfire could cause catalyst damage.
l To prevent catalytic converter damage, the PCM moni tors engine’ misfire.l
H e a d g a s k e t f a i l e d
l The PCM monitors for misfire during most engine ope rating conditions., h e a d
When a misfire is detected, the PCM stores a diagno
stic trouble code and causes thel
Injector failedl to either flash or illuminate continuously during active misfire.
Range of Check
l MAP voltage is less than
l Engine speed is between 2200 and l Engine coolant temperature is greater than l Vehicle speed less than Set Conditionl 1000 Rev Misfire l
Wiring harness and connectors failed
6
The PCM detects misfire in more than 1.6% of the en gine cycles in a 1000 revolutionperiod. 200 Rev MisfireThe PCM detects misfire in more than 15% of the eng ine cycles in a revolution period.
NG
OK
OK
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Check the following items.
l Check the spark plug, spark plug cables.
l Check compression pressure.
l Check the cylinder head gasket and intake manifold gasket for damage.