(AJUDA GERAL): Manual - Testando o sistema D-Jetrônic

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(AJUDA GERAL): Manual - Testando o sistema D-Jetrônic Empty (AJUDA GERAL): Manual - Testando o sistema D-Jetrônic

Mensagem por Karl Fass em Ter 07 Ago 2012, 14:56

TEST CHART
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Revision #1 Page 1 of 9 R.E.S. SYSTEMS
D-Jetronic
ALL MEASUREMENTS ARE MADE ON THE TERMINALS OF THE DISCONNECTED WIRING
HARNESS PLUG TO THE CONTROL UNIT (ECU) WITH IGNITION OFF UNLESS
OTHERWISE INDICATED.
Voltage Supply
OPERATE: Ignition
MEASURE: Voltage supply to the ECU.
VALUE: 11-12.5 V between terminal 16 and system ground at
terminal 11 of ECU plug.
DEVIATION: No reading: open circuit in cable from main relay to ECU,
main relay does not energize, ignition switch defective
(check for voltage at terminals 86, 30/51 and 87 of relay).
Check cable 16 connecting main relay and ECU. Check
cable 11 to ground.
Voltage below 11 V: Contact resistance in cable 16 or 11 or
at relay contacts.
Also check cable 24 for voltage supply as described above
for cable 16.
OPERATE: Starter
MEASURE: Voltage between terminal 50 of starter and ground.
VALUE: 9-12 V.
DEVIATION: No reading, but starter operates: open circuit from starter
terminal 50 to ECU (check cable 18).
No reading, starter does not operate: ignition switch
defective or open circuit in cable.
Voltage below 9 V: battery low or voltage drop in cable
from ignition switch to starter terminal 50 (check cable).
TEST CHART
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Revision #1 Page 2 of 9 R.E.S. SYSTEMS
D-Jetronic
Pressure Sensor
MEASURE: Resistance between pressure sensor winding and ground.
VALUE: Infinite resistance (¥ W) between ECU plug terminal 11
(ground) and terminals 7, 8, 10, and 15 in turn.
DEVIATION: Zero resistance (continuity): Short circuit to ground in
windings or cable. If meter at ECU terminals shows ¥ W
with plug removed from sensor, replace sensor. Check
cables 7, 8, 10, and 15 for short to ground.
Resistance lower than ¥ W but not 0W: Damage to cable
Insulation.
MEASURE: Resistance of primary windings.
VALUE: About 90W between terminals 7 and 15 of ECU plug.
DEVIATION: Resistance considerably lower: Damage to insulation.
Pull plug out of sensor and if tester reads ¥ W. replace
sensor.
Resistance 0W (continuity): Short to ground, short in
primary windings. Pull plug from sensor, if meter reads
¥ W, replace sensor.
Resistance considerable higher: High contact resistance
(test plugs and cables).
Resistance ¥ W: Open circuit. Bridge terminals 7 and 15
at pressure sensor plug. If tester at ECU wiring harness
terminal 7 and 15 reads zero, replace pressure sensor;
if ¥ W, check cables.
MEASURE: Resistance of secondary windings.
VALUE: About 350 W between terminals 8 and 10 of ECU plug.
DEVIATION: As above under “primary windings.” For resistance ¥ W,
bridge terminals 8 and 10 at the pressure sensor plug.
Resistance considerably higher: High contact resistance
(test plugs and cables).
TEST CHART
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Revision #1 Page 3 of 9 R.E.S. SYSTEMS
D-Jetronic
THROTTLE VALVE SWITCH
OPERATE: Depress accelerator slowly.
MEASURE: Full load enrichment function.
VALUE: Alternating reading ¥/0W with meter connected between
terminal 9 and system ground at terminal 11 of ECU plug.
DEVIATION: If only 0W reading is shown, replace throttle valve system.
OPERATE: Accelerator in idle position.
MEASURE: Function of idle contacts.
VALUE: 0W (continuity) between terminal 17 and system ground
at terminal 11 at ECU plug.
DEVIATION: Resistance ¥ W: throttle valve switch incorrectly adjusted.
Adjust according to appropriate section in “Component
Removal and Replacement.” Open circuit in cable (check
cables). If direct reading at terminals 47 and 17 of throttle
valve switch still gives infinite resistance (¥ W), replace
throttle valve switch.
OPERATE: Accelerator slightly depressed.
MEASURE: Function of idle contacts.
VALUE: ¥ W between terminals 17 and 11 of ECU plug.
DEVIATION: Resistance 0W (continuity): throttle valve switch incorrectly
adjusted or short circuit in cables. Pull plug from
throttle valve switch. If meter at ECU plug still reads 0W,
cable is defective. Otherwise adjust or replace throttle
valve switch.
TEST CHART
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Revision #1 Page 4 of 9 R.E.S. SYSTEMS
D-Jetronic
Temperature Sensor I (intake manifold)
MEASURE: Resistance of the temperature sensor.
VALUE: About 300W at 68°F between terminals 1 and 13 of ECU
plug. At 14°, 860-1200W; at 68°f, 260-340W; at 122°F,
90-130W.
DEVIATION: If meter reads ¥ W, check sensor directly at plug. If sensor
checks out OK, replace cables. If tester shows 0W (continuity)
at sensor terminals, replace sensor.
If meter reads 0W, pull plug from sensor. If meter then
reads ¥W, replace sensor. Otherwise replace cables.
Temperature Sensor II (cylinder head)
MEASURE: Resistance of the temperature sensor.
VALUE: About 2.5W at 68°F between ECU plug terminals 11
(ground) and 23. At 14°F, 7-12kW; at 68°F 2-3kW; at 122°F,
.68-1kW.
DEVIATION: As above for Temperature Sensor I.
Trigger Contacts In Distributor
OPERATE: Starter to turn engine over.
MEASURE: Correct function of trigger contacts in distributor.
VALUE: Alternating reading between ¥ and 0W with meter connected
between terminal 12 and terminals 21 and 22
in turn.
DEVIATION: If needle remains at ¥ W or 0W check terminals 12, 21 and
22 at the distributor. If terminals and cables to ECU are
OK, replace trigger contacts.
TEST CHART
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Revision #1 Page 5 of 9 R.E.S. SYSTEMS
D-Jetronic
Injection Valves
MEASURE: Resistance of coil windings in valves.
VALUE: 2.4kW at 68°F between system ground at ECU plug terminal
11 and terminals 3, 4, 5 and 6 in turn.
DEVIATION: Resistance zero: short circuit in winding or cable. Pull
plug out of injection valve; if meter at ECU plug shows
¥ W, replace valve, otherwise replace wiring harness.
Resistance ¥ W: open circuit in winding or cable. Check
cable for continuity. If OK, replace valve.
Resistance over 3W: check ground cable from injection
valves to engine.
Visual check of injection valves: check connections, check
grey caps pointing to rear on cylinders 2 and 4, black caps
towards front. Check that protective caps are pulled over
plugs.
TEST CHART
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Revision #1 Page 6 of 9 R.E.S. SYSTEMS
D-Jetronic
Fuel Pump, Pressure Regulator and Relay
OPERATE: Turn on ignition and bridge ECU plug terminal 19 to
system ground at terminal 11 to energize relays and
operate fuel pump. Connect pressure gauge as described
in section “Component Removal and Replacement.”
Gauge remains connected for all remaining test steps.
MEASURE: Pressure in fuel line and function of pressure regulator.
VALUE: 2.0 - 2.2kgf/cm2 (28.5 - 30.8 psi)
DEVIATION: No pressure build-up (pump does not start): pull plug
from pump and measure voltage at plug contacts. If 12 V,
pump is defective. If 0 V, check pump relay. If relay is
operating, then check cable from relay terminal 87 to
pump. If cables are OK, relay is defective. If relay is not
operating, check cable from main relay terminal 87 to
pump relay terminal 86 or from pump relay terminal 85
to cable 19 of the wiring harness (in engine compartment)
for continuity. If cables check OK, replace pump relay.
Pressure above or below 28-30 psi: pressure regulator
incorrectly adjusted; adjust as described in “Component
Removal and Replacement.” If adjustment not possible,
replace unit.
TEST CHART
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Revision #1 Page 7 of 9 R.E.S. SYSTEMS
D-Jetronic
Fuel Leakage in System
OPERATE: Turn on ignition and briefly bridge terminals 19 and 11 of
ECU plug to energize relays and operate fuel pump.
MEASURE: Leaks in fuel system.
VALUE: After removing terminal bridge, pressure may drop from
nominal value back to .8 kfg/cm2 (11.4 psi). After this,
any further pressure drop must be very slow.
DEVIATION: After removing bridge, pressure drops immediately to
below 1 kfg/cm2 (14.2 psi) or drops to zero: leak in sysstem
from fuel pump to pressure regulator. Check all
hoses and connections and injection valves for leads.
Build up pressure several times during test as required.
Injection Valve Fuel Leakage
Perform this test only if valves are suspected of leakage,
since injectors must be removed.
OPERATE: Starter and energize one set of valves at a time by bridging
ECU plug terminal 16 and terminals 3, 4, 5, and 6 in
turn.
MEASURE: Visual inspection of spray pattern.
DEVIATION: Check for leaks. the injector orifice may become wet, but
no more than two drops should form on the valve per
minute.
TEST CHART
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Revision #1 Page 8 of 9 R.E.S. SYSTEMS
D-Jetronic
Cold Start Valve And Thermo-Switch
With engine temperature above 32-50°F.
OPERATE: Starter.
MEASURE: Function of thermo-switch.
VALUE: Pressure reading on gauge should not drop perceptibly.
DEVIATION: If pressure falls when starter is operated, thermo-switch
is defective.
OPERATE: Starter with thermo-switch grounded.
MEASURE: Function of cold-start valve.
VALUE: Pressure reading on gauge should drop while cold-start
valve injects.
DEVIATION: If pressure does not drop when starter is operated, check
cable 31 from cold-start valve to starter terminal 50 for
continuity. If cable OK, check cold-start valve winding
resistance at contacts on valve: 4.2W at 68°F.
With engine temperature below 32-50°F.
OPERATE: Starter (thermo-switch connected normally).
MEASURE: Function of thermo-switch.
VALUE: Pressure reading on gauge should drop slowly.
DEVIATION: If pressure does not drop, thermo-time switch or coldstart
valve defective. Test cold-start valve as described
above.
TEST CHART
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Revision #1 Page 9 of 9 R.E.S. SYSTEMS
D-Jetronic
Thermo-Time Switch
Engine temperature above 23-41°F.
OPERATE: Starter.
MEASURE: Function of thermo-time switch.
VALUE: Pressure reading on gauge should not drop perceptibly.
DEVIATION: If pressure falls when starter is operated, thermo-time
switch is defective.
OPERATE: Starter with thermo-time switch terminal W grounded.
MEASURE: Function of cold-start valve.
VALUE: Pressure reading on gauge should drop while cold-start
valve injects.
DEVIATION: If pressure does not drop when starter is operated, check
cable 31 from cold-start valve to starter terminal 50. If
cable OK, check cold-start valve winding resistance at
contacts on valve: 4.2W at 68°F.
Engine temperature below 23-41°F.
OPERATE: Starter (thermo-time switch connected normally).
MEASURE: Function of thermo-time switch.
VALUE: Pressure reading on gauge must drop.
DEVIATION: If pressure does not drop, thermo-time switch or coldstart
valve defective. Test cold-start valve as described
above.
END OF TEST. TURN OFF IGNITION AND REMOVE PRESSURE GAUGE.

_________________
Abraços,
Tio Fass

C126 500SEC  1983
W108 280S 1972
W202 C280 1995
(AJUDA GERAL): Manual - Testando o sistema D-Jetrônic G9b



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Karl Fass
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