engine MITSUBISHI SPYDER 1990 Service Repair Manual

17-16ENGINE AND EMISSION CONTROL Auto-cruise Control System
INSPECTION PROCEDURE 9
Auto-cruise control main switch illumination light does not
illuminate. Probable cause
A malfunction of the auto-cruise control main switc
h, or connector may exist.l
Malfunction of the auto-cruise control mainswitch.l Malfunction of the connector.
l Malfunction of the harness.
Auto-cruise control main switch check(Refer to Replace
OK
Measure at auto-cruise control main
switch connector
lDisconnect the connector and mea-sure at the harness side.
l Voltage between terminal (2) and
groundOK: Battery positive voltage
II
OK
Check trouble symptom.
N Gpower supply. Repair, if necessary.
Check the harness between the
auto-cruise control main switch and
rheostat. Repair, if necessary.
INSPECTION PROCEDURE 10
Auto-cruise control indicator inside combination me ter does
not illuminate. (However, auto-cruise control is no rmal.)Probable cause
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l
Malfunction of the bulb.
l Malfunction of the
l Malfunction of the connector.
l Malfunction of the PCM.
(Refer to
illuminate when terminal (22) of PCM connector A-l 06 is

ENGINE AND EMISSION CONTROL Auto-cruise System
TROUBLESHOOTING ENGINE (TURBO) AND ENGINE>
DIAGNOSTIC TROUBLESHOOTING FLOW
Does not
(Refer to (Refer to
No diagnostic troubleDiagnostic troubleNo diagnostic
code or can’t code displayedtrouble code
with scan tool
(Refer to
NOTE
Before carrying out trouble diagnosis, check to be
sure that all of the following items are normal.
1. Is the vacuum hose correctly installed and undam aged?
2. Are the auto-cruise, accelerator, and throttle c ables routed correctly?
3. Do the link assembly and cables move smoothly?
4. Is the play of each cable within its standard va lue?
DIAGNOSTIC FUNCTION
HOW TO READ DIAGNOSTIC TROUBLE CODES
When using the scan tool
1. Connect the scan tool to the data link connector .
Caution
Turn the ignition switch off before or
connecting the scan tool.
2. With the ignition switch in the ON
turn the
auto-cruise control main switch to ON and take a
of the diagnostic trouble codes.
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ENGINE AND EMISSION CONTROL Auto-cruise Control
When using a voltmeter
1.Use the special tool to connect a voltmeter between the
ground terminal and the diagnostic output terminal of
d a t a l i n k c o n n e c t o r .
2.In the same way as when using the scan tool, turn t he
ignition switch to ON and turn on the auto-cruise c ontrol
main switch. Then take a reading of the diagnostic trouble.
codes from the movement of the needle on the voltme ter.
HOW TO READ DIAGNOSTIC TROUBLE CODES FROM A VOLTMET ER
Example of diagnostic trouble code voltage waveformNormalvoltage waveform
For diagnostic trouble code No. 24
NOTE
Other on-board diagnostic items are also output as voltage waveforms corresponding to diagnostic troub le code
numbers.
HOW TO ERASE DIAGNOSTIC TROUBLE CODES
The diagnostic trouble codes can
erased by disconnecting the cable from the battery for 10 seconds
or more and then reconnecting it, or by the followi ng procedure.
1. Turn the ignition switch to ON.
2.With the SET switch at the ON position, turn the ma in switch to ON, and within 1 second after this,
turn the RESUME switch to ON.
3. With the SET switch once more at the ON position , turn the stop light switch ON for a continuous
period of 5 seconds or more.
Auto-cruise control switch
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HOW TO READ INPUT SWITCH CODES
1. Connect the scan tool or a voltmeter to the data link
connector. (Refer to
2.With the ignition switch in the ON position, turn t he S E T
switch to the ON position.
3.Within 1 second after turning the auto-cruise contr ol main
switch to ON, turn the RESUME switch to ON.
4. Operate each switch listed in the input inspecti on table
and take a reading of the input switch codes with t he
scan tool or the fluctuation of a voltmeter.
NOTE
These codes are output as voltage waveforms in the
same way as above.

ENGINE AND EMISSION CONTROL Auto-cruise Control’
Code 2 Vehicle speed signal system
[Comment]l Malfunction of the vehicle This diagnostic trouble code is output if the vehic le speed signals from the vehicle speed sensor l of connectorare not input to the auto-cruise control-ECU when t he vehicle speed is 40 km/h (25 mph) l
Malfunction of the harness
or more. l Malfunction of the auto-cruise
Check the vehicle speed sen(Refer to GROUP 54 CombinationMeter.)
1. NG
Measure at the vehicle speed sensor connector Check the following connector. l Disconnect the connector, and measure at the
harness side.O K
1. Voltage between 1 and ground (Ignition switch: ON)
NG
System voltage
2.Voltage between 3 and ground2. N G(Ignition switch: ON)
OK: 4.6 5.2 3.Continuity between 2 and ground3. N G
OK: Continuity
OK
Check trouble symptom.
N G
Check the harness between the speed sensor
Check the following
OKNG
Check trouble symptom.
NG
Check the harness between the auto-cruise ECU and the vehicle soeed sensor connector.
OKNG
Replace the auto-cruise control-ECU.
and ignition switch connector
OK
Check the ignition switch.
(Refer to GROUP 54 , ,
Check the harness between the vehicle speed sensorand the ground. Repair, if necessary.
Code Autocruise vacuum pump power supply systemProbable cause
[Comment]
This code will be output when the drive signals for the auto-cruise vacuum pump release valve,
control valve and motor are not input to the auto-c ruise control-ECU.l
the stop light l
Malfunction of the connector
l
l of the auto-cruise
at the auto-cruise vacuum
l Disconnect the connector and
l Voltage between terminal (1) and
OKN G Check the harness between the cruise vacuum pump and the cruise control-ECU.
and
Replace the auto-cruise control-ECU.
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17-22ENGINE AND EMISSION CONTROL Auto-cruise Control System
Code Auto-cruise switch Probable cause
l Malfunction of the auto-cruise control switch
This diagnostic trouble code is output if the RESUME switch or SET switch remains ON.
Replace the auto-cruise control
Code 6 Auto-cruise control-ECU Probable cause
[Comment]l Malfunction of the auto-cruise control-ECU
This diagnostic trouble code is output if there is an abnormality in the CANCEL hold circuit
or the microprocessor monitor circuit in the auto-c ruise control-ECU.
Replace the auto-cruise
Code Throttle position sensor system Probable cause
[Comment]l
Malfunction of the throttle position sensor
This diagnostic trouble code is output if a voltage of 1.5 or more when the closed throffle l
Malfunction of the connectorposition switch is ON or 0.2 or less when the closed throttle position switch i s OFF is outputlMalfunction of the harness
for a continuous period of 4 seconds or more. l
Malfunction of the auto-cruise control-ECU
trouble code No. 14 outputfrom the powertrain control module?
OK
Check troubleNGsympl Inspect the harness between the position sensor and cruise control-ECU
OK
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Replace the auto-cruise control-ECU.

ENGINE AND EMISSION CONTROL Auto-cruise Control
INSPECTION CHART FOR SYMPTOMS
Communication with
scan tool is not
possible. Communication with systems is not possible.
Communication with auto-cruise control-ECU only
is not possible.1
2
Input switch inspection using the scan tool is not possible. (However,
diagnostic inspection is possible.)3 .
Auto-cruise control When brake pedal is depressed 4 does not cancel. When clutch pedal is depressed
When select lever is set to range
When CANCEL switch is set to ON
5
17-26
I 7 17-27
Trouble symptomInspection
procedure No.Reference page
The diagnosis result displayed on the scan tool is normal even though
auto-cruise control cannot be set.
Auto-cruise control cannot be set.I9
Hunting (repeated acceleration and deceleration) oc curs at the set vehicle
speed.I1
When the auto-cruise control main switch is ON, the switch indicator on the
instrument panel does not illuminate. (However, aut o-cruise control is normal.)
Auto-cruise control main switch illumination light does not illuminate.111 7 - 2 9 , .
1217-29
Auto-cruise control indicator light inside combinat ion meter does not illuminate.
(However, auto-cruise control is normal.)13
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17-24ENGINE AND EMISSION CONTROL Auto-cruise Control System
INSPECTION PROCEDURE: FOR TROUBLE SYMPTOMS
INSPECTION PROCEDURE 1
Communication with scan tool is not possible. (Comm unication with
all systems is not possible.)
[Comment]A defect in the power supply system (including grou nd) for the diagnostic line may be present.
Refer to GROUP
INSPECTION PROCEDURE 2 l
Malfunction of the connector.
l Malfunction of the harness.
Communication with scan tool is not possible.
(Communication with auto-cruise control-ECU only is not
possible.) Probable cause
[Comment]l
Malfunction of the auto-cruise control mainswitch switch.ground circuit may be present. l
Malfunction of the connector.
l Malfunction of the harness.
l Malfunction of the auto-cruise control-ECU.
1. Auto-cruise control main switch circuit malfunct ion
Auto-cruise control main switch checkN G Repair to
OK
N G Measure at auto-cruise control main switch connector lDisconnect the connector and mea-sure at the harness side.
l Voltage between the terminal (1)
and around
OK: Battery positive voltage
Check troublesymptom.
. Repair 24, and
Check the harnesses between the auto-cruise control main switch and
ground or between the auto-cruise
control main switch and auto-cruise
control-ECU. Repair, if
2. Auto-cruise control-ECU ground circuit malfuncti on
Measure at auto-cruise control-ECU
connector
lDisconnect the connector and mea-sure at the harness side.lContinuity between terminal (6) and
ground, terminal (8) and ground and
between terminal (14) and ground.
OK: Continuity
OK
Check the harness between the
auto-cruise control main switch and power supply. Repair, if necessary.
Check the following connector:
OK
Check trouble symptom.
OK
Check trouble symptom. . Replace the auto-cruise control-ECU.
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ENGINE AND EMISSION System
.,
INSPECTION PROCEDURE 3
Input switch inspection using the scan tool is pdssible.
(However, diagnostic inspection is possible.)
I
[Comment]A malfunction of auto-cruise control switch circuit system may be present.l
Malfunction of the auto-cruise control l Malfunction of the clock spring .
l of the connector.
l Malfunction of the harness.
.
NG
(Refer to
Measure at clock spring connector
l sure at the harness side
l Voltage between terminal (2) and
groundOK: Battery positive voltage
OK
Check trouble symptom.
C h e c k t r o u b l e spring and auto-cruise
INSPECTION PROCEDURE 4
When brake pedal is depressed, auto-cruise control does not
cancel.Probable , ,
[Comment]A malfunction of stop light switch or a malfunction of stop light circuit may be present.l
Malfunction of the stop light switch.
l Malfunction of the connector.
l Malfunction of. the
l Malfunction of the auto-cruise control-ECU.
Does stop
illuminate?
No
Replace the auto-cruise control-ECU.
lDisconnect the connector and mea-sure at the harness side.
Check trouble symptom.Check the following connectors:
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17-26E N G I N E A N D E M I S S I O N C O N T R O L Auto-cruise Control System
INSPECTION PROCEDURE 5
When clutch pedal is depressed, auto-cruise control does not
cancel.Probable cause
or clutch circuit may be present. l
Malfunction of the clutch pedal position switch.l
Malfunction of the connector.
l Malfunction of the
l Malfunction of the auto-cruise control-ECU.
Clutch pedal position switch check
(Refer to
Measure at clutch pedal position switchconnectorlDisconnect the connector and mea-sure at the harness side.
l Voltage between terminal (2) and
groundOK: positive voltage
Check the following
OK.Check trouble symptom.NG Check the harness between the clutchpedal position switch and auto-cruise
control-ECU. Repair, if necessary.
Check trouble symptom.Inspectthe harness between theclutchpedal position switch and ground.
NG
Replace the auto-cruise control-ECU.
INSPECTION PROCEDURE 6
When select lever is set to range, auto-cruise control does
not cancel. Probable cause
[Comment]The cause is probably an open-circuit in the output signal circuit in range.l
Malfunction of the position switch
l Malfunction of the connector.
l Malfunction of the harness.
l Malfunction of the auto-cruise control-ECU.
Park/neutral position switch check
Measure at park/neutral position switch -- Starter relay continuity check (Refer to check (Refer toconnector A-l 01.GROUP 16 Starting System.)
ing System.)
l Disconnect the connector and
measure at the harness side.OK
l Voltage between terminal (6) andNG
ground Engine>l Voltage between terminal (5) and and
ground Engine>OK
OK: Battery positive voltage
Check trouble symptom. Check the harness between-the neutral position switch control-ECU. Repair, if necessary.
Check the harness between the park/ Replace control-ECU.,.neutral position switch and ground.
neutral position switch and ground.,
NGNG
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ENGINE AND EMISSION CONTROL Control. System
INSPECTION PROCEDURE 7
When auto-cruise control CANCEL switch is set to ON,
auto-cruise control does not cancel.
[Comment]An open-circuit in the circuit inside the CANCEL sw itch may be present.
Replace the auto-cruise control switch.
INSPECTION PROCEDURE 8l the
The diagnostic result displayed on the scan tool is normal
even though auto-cruise control cannot be set.
[Comment]Because of an open-circuit in the battery backup ci rcuit system, the fail-safe function preventsdiagnostic trouble codes from being memorized and d isplayed even though auto-cruise controlis canceled.
Probable cause
l Malfunction of the connector.
l Malfunction the harness.
l Malfunction of the
Measure at auto-cruise control-ECU
connector
l sure at the harness side.lVoltage between terminal (16) and
around
Battery positive voltage
OKCheck the harness between the
auto-cruise control-ECU and power
supply. Repair, if necessary.
Check the following connector:
Replace the auto-cruise control-ECU.
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