Daewoo CIELO EURO III Manual page 414

1F – 244 ENGINE CONTROLS
ROUGH ROAD SENSOR SOURCE NOT DETECTED (1.5L SOHC)
Circuit Description
The Engine Control Module (ECM) identifies engine
misfire by detecting variations in crankshaft speed.
Crankshaft speed variations can also occur when a ve-
hicle is operating over a rough road. The ECM receives
rough road signal by gravity sensing rough road (G) sen-
sor or Electronic Brake Control Module (EBCM) if
equipped with the Anti-Lock Brake System (ABS). The
ABS can detect if the vehicle is on the rough surface
based on wheel acceleration/deceleration data supplied
by each wheel speed sensor. This information sent to
the ECM by EBCM through Pulse Width Modulation
(PWM) serial data line. The G sensor is vertical low g–
acceleration sensor. By sensing vertical acceleration
caused by bumps or portholes in the road, the ECM de-
termine if the changes in crankshaft speed are due to
engine misfire or are driveline induced. If the ECM can
not receive any of those signal, a historic Diagnostic
Trouble Code (DTC) will be stored.
Conditions for Setting the DTC
ECM cannot detect any rough road source.
Engine run time is greater than or equal to 10 sec-
onds.
Action Taken When the DTC Sets
The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
DIAGNOSTIC TROUBLE CODE (DTC) P0317
The ECM will store conditions which were present
when the DTC set as Failure Records data only. This
information will not be stored as Freeze Frame data.
A history DTC is stored.
Conditions for Clearing the MIL/DTC
A history DTC will clear after 40 consecutive warm-up
cycles without a fault.
The DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
An open signal circuit of G sensor or open PWM serial
data line between the ECM and the EBCM will be the
cause of this DTC.
Test Description
The number(s) below refer to specific step(s) on the
diagnostic table.
1. On-Board Diagnostic (EOBD) System Check
prompts the technician to complete some basic
checks and 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.
10. The replacement ECM must be reprogrammed. Re-
fer to the latest Techline procedure for ECM repro-
gramming.
KAA1F390
DAEWOO T-154 BL2,3