1990 MITSUBISHI SPYDER sensor

ENGINE , Troubleshooting
EEPROM Write DeniedProbable.
[Comment)l Unsuccessful attempt to write to an EEPROM location by the control module.l
PCMI
Replace the PCM.
Scan tool 57
Code General scan Intake Air Temperature
No.Voltage Low
23
[Comment]l Sensor to Backgroundl Sensor internally shortedlWhen the fuel system is in the open loop mode, the heated oxygen sensor cannot be
l PCM failed
used for injector pulse width calculation.
l In this instance, the system uses information on ai r mass to determine the correct
,
width necessary to achieve the proper air/fuel rati o.lBecause air mass is related to temperature, informa tion from the intake air temperature ,
sensor is necessary.
Range of Check
l Ignition switch: ON
Set Condition
lIntake air temperature sensor output voltage is les s than 0.2 for 3 seconds.
N GCheck the intake air temperature sensor. (Refer to Replace
OK
Repair
OK
Check trouble symptom.
N G
Check the harness wire temperature sensor connector.
OK
Repair
Replace the PCM.
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Scan tool 58
Code General scan tool Air Temperature Senspr
No.Voltage High
23
[Comment]Background
lWhen the fuel system is in the open mode, the heated oxygen sensor cannot be
used for injector pulse width calculation.
lIn this instance, the system uses on air mass to determine the correct pulse
width necessary to achieve the proper air/fuel rati o.
lBecause air mass is related to temperature, informa tion from the intake air temperature
sensor is necessary.
Range of Check
l Ignition switch: ON
Set Condition
l air temperature sensor output voltage is more than for 3
Check the intake air temperature sensor. (Refer to Replace
Measure at the intake air temperature sensor connec tor
lDisconnect the connector, and measure at the harness side.
l Continuity between and ground
OK: Continuity
OK
Sensor signal circuit open Sensor internally open
l Sensor ground circuit open
l PCM failed
Check the wire between the PCM the intake temperature connector. if necessary.
Check the following
OK
NG Repair
Check trouble symptom.
N G NGCheck the harness wire between the PCM and the inta ke air temperature sensor connector.
N G
Replace the PCM.
Repair
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ENGINE
Scan tool 59. . ,
Knock Sensor CircuitNo.
16
[Comment]
Background
lThe sensor consists of a material that constantly vibrates, sending asignal to the PCM when the engine is operating.lWhen the signal exceeds a threshold, the PCM retards engine ignition timing to reduce
Set Condition
l Knock sensor signal below minimum acceptable thresh old voltage.
Knock sensor output voltage is above 5.0 volts.
l Knock sensor lOpen or shorted knock sensor l
. .
,
I
Measure at the knock sensor connector Check the following lDisconnect the connector, and measure at the harnes s side.
l Continuity between 2 and ground
OK: Continuity,
OK
if.
NG.
Repair .
OK
Check trouble symptom.
N G Repairconnector.
OK
Replace the knock sensor.
.
Check trouble symptom.
NG
Replace the PCM.
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ENGINE (NON-TURBO)>
NG Replace
Scan tool 62
Code General scan tool Upstream Shorted to Volt;
No.
21
[Comment]l Heated oxygen sensor failedBackgroundl W i r i n glUpstream heated oxygen sensor requires a heater cir cuit for proper operation.
l PCM,
l The heater circuit is supplied with battery voltage through the
relay relay):lA failure in the sensors heater circuit prevents it from providing accurate data to the PCM.l the PCM monitors more than 1.2 volts, the sensor h as shorted to heater circuit voltage.Range of Checkl Two or more minutes after the engine startsl Engine coolant temperature: or moreSet Conditionl Heated oxygen sensor output voltage is more than 1. 2 for 3 seconds.
OK
OKNG Repair
Check trouble symptom.
NGNGCheck the harness wire between the PCM and the heat ed oxygen Repairsensor (front).
OK
Replace the PCM.
Scan tool 68
Code General scan tool PCM Failure
No. Communications
53
[Comment]Set Condition
l There is no communication between in the control module.
Probable cause
l PCM failed
the PCM.
Probable cause
[Comment] BackgroundlBattery temperature input is used to adjust the gen erator charging rate based upon the
ambient temperature around the battery.
Range of Check
l
switch: ON
Set Condition
lThe sensor voltage is not within the acceptable ran ge of 0.3 to 4.9 volts for 3 seconds
or more. l
Battery temperature sensor failed
l PCM failed
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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E N G I N E
[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 relay) and tests for the heated oxygen sensor operation.
Range of Check
l 5 seconds or more after turning the ignition switch to OFF.
l Battery positive voltage: 10
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 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.
1. NG
Measure at the heated oxygen sensor (rear) connecto r
lDisconnect the connector, and measure at the harnes s side.
SCAN TOOL Actuator test 10
relay (ASD relay) everyapprox. 1. Voltage between 3 and ground [Measure with the relay
(ASD relay) on]
OK: Battery positive voltage
2. Continuity between 4 and ground
OK: Continuity
OK
2. NG l
Heated oxygen sensor heater
l harness and
. .
Check the harness wire between (ASP the heated oxygen sensor
Check the harness wire between the heated oxygen s ensor and
the ground. Repair, if necessary.
NG Repair
Check trouble symptom.
OK
NG
Replace the heated oxygen sensor (rear).
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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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