Daewoo CIELO EURO III, Manual

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1F – 233 ENGINE CONTROLS
DAEWOO T-154 BL2,3
Conditions for Clearing the MIL/DTC
The MIL will turn off after three (four –
1.5L SOHC) consecutive ignition cycles in which the
diagnostic runs without a fault within the freeze frame
conditions that the DTC failed.
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
An intermittent can also be the result of a defective re-
luctor wheel. Remove the CKP sensor and inspect re-
luctor wheel through sensor mount hole. Check for
porosity and condition of wheel. If DTC is intermittent,
refer to “Symptoms Diagnosis” in this section.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Table.
1. The On-Board Diagnostic (EOBD) System Check
prompts the technician to complete some basic
checks and to store the freeze frame and failure re-
cords data on the scan tool if applicable. This
creates an electronic copy of the data taken when
the malfunction occurred. The information is then
stored on the scan tool for later reference.
3. A visual/physical inspection should include checking
the following components:
The wiring for proper connections, pinches or
cuts.
The ECM grounds for being clean and tight.
The vacuum hoses for splits, kinks, and proper
connections as shown on the Vehicle Emission
Information label.
Check thoroughly for any type of leak or restric-
tion.
Check for air leaks at the throttle body mounting
area and intake manifold sealing surfaces.
5. When all the accumulators are relatively equal, then
the misfire is being caused by something that affects
the entire engine. When they are not, then the mis-
fire is being caused by something that is specific to
two or more cylinders.
6. Whenever the misfire is not present operating the
vehicle may be necessary to duplicate the condi-
tions in the Freeze Frame Data in order to detect
misfire. Depending on the engine load, the condi-
tions may have to be maintained for up to 20 sec-
onds. Whenever the misfire accumulators start to
increment, then misfire is present. A history misfire
counter will store the number of misfires that have
occurred until the DTC is cleared.
8. Check fuel for water, alcohol, etc.
9. A basic engine problem that affects all cylinders is
the only possibility at this point. (Cam timing, throttle
body leak, restricted airflow, etc.)
11. Tests the ignition system voltage output using a
spark tester.
12. Replace any spark plugs that are worn, cracked or
fouled.
13. Checks for voltage at the ignition feed circuit.
18. Whenever the driver circuit is shorted to ground, the
light will be on steady. When the driver circuit is
shorted to voltage or open, the light will be off.
19. Since voltage is supplied to the fuel injector on a
single circuit, the malfunction could only be a poor
connection or open in the fuel injector harness. An
open before the harness would result in a “Engine
Cranks But Will Not Run” complaint.
27. Before replacing the ECM, check terminals for
improper mating, broken locks, or physical damage
to the wiring harness. The replacement ECM
must be reprogrammed. Refer to the latest Techline
procedure for ECM reprogramming.