Daewoo MATIZ Service Manual page 354

1F – 256 ENGINE CONTROLS
DIAGNOSTIC TROUBLE CODE (DTC) – P1538 A/C COMPRESSOR RELAY LOW
Circuit Description
The A/C system uses an A/C refrigerant pressure sen-
sor mounted in the high pressure side of the A/C refrig-
erant system to monitor A/C refrigerant pressure. The
engine control module (ECM) uses this information to
turn ON the engine coolant fans when the A/C refriger-
ant pressure is high and to keep the compressor disen-
gaged when A/C refrigerant pressure is excessively high
or low.
Conditions for Setting the DTC
D A/C compressor relay circuit short to ground or open.
Action Taken When the DTC Sets
D The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
D The ECM will store conditions which were present
when the DTC was set as Failure Records data only.
D This information will not be stored in the Freeze
Frame data.
VOLTAGE
Conditions for Clearing the MIL/DTC
D A history DTC will clear after 40 consecutive warm-up
cycles without a fault.
D DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
Inspect harness connectors for backed-out terminals,
improper mating, broken locks, improperly formed or
damaged terminals, and poor terminal-to-wire connec-
tion at the ECM.
Inspect the wiring harness for damage. If the harness
appears to be OK, observe the A/C pressure display on
the scan tool while moving the connectors and wiring
harnesses related to the ACP sensor. A change in the
A/C pressure display will indicate the location of the
fault.
If DTC P1538 cannot be duplicated, reviewing the Fail
Records vehicle mileage since the diagnostic test last
failed may help determine how often the condition that
caused the DTC to set occurs. This may assist in diag-
nosing the condition.
MAA1F310
DAEWOO M-150 BL2