Excelsior-HENDERSON HCX 1999, Service Handbook

Page: 60 / 474

4-10
6999-0003 7/15/99
ENGINE CONTROL SYSTEM
MANAGING SYSTEM DIAGNOSTICS
Each sensor or component has an acceptable operating
voltage or resistance range that the ECM recognizes.
When a sensor or component does not operate in its
acceptable voltage range, the ECM records this occur-
rence as an event. When the number of events reaches
a system-defined threshold, the ECM records a fault
code, records a table of engine data, and illuminates the
check engine lamp. All fault codes are stored in memory,
but not all illuminate the check engine lamp.
When fault-producing conditions cease, and after a suf-
ficient number of warm-up cycles, the ECM will extin-
guish the check engine lamp and clear fault codes from
memory. A warm-up cycle begins with an initial engine
temperature below 120
°
F, followed by a warm-up above
160
°
F, followed by engine shutdown. After forty warm-
up cycles without an event, the ECM will remove a fault
code and engine data from memory.
The ECM stores the following fault codes:
P0105 Barometric Pressure Sensor Fault P0335 Crankshaft Sensor Circuit Fault
P0112 Air Temperature Sensor Short to Ground P1335 Crankshaft Sensor Signal Fault
P0113 Air Temp Sensor Open Circuit/Short to Power P0351 Ignition Coil 1 Circuit Fault
P0117 Engine Temperature Sensor Short to Ground P0352 Ignition Coil 2 Circuit Fault
P0118 Eng. Temp Sensor Open Circuit/Short to Power P1352 Ignition Coil 1 Open Circuit/Short to Ground
P0119 Engine Temperature Sensor Voltage High P1353 Ignition Coil 2 Open Circuit/Short to Ground
P0122 Throttle Position Sensor Low Input Voltage P1355 Ignition Coil 1 Short to +12V
P0123 Throttle Position Sensor High Input Voltage P1356 Ignition Coil 2 Short to +12V
P0170 Air/Fuel Feedback Fault P1385 Tachometer Circuit Fault
P1171 Air/Fuel Feedback Maximum Rich P1386 Tachometer Open Circuit/Short to Ground
P1172 Air Fuel Feedback Maximum Lean P0444 Purge Valve Open Circuit/Short to Ground
P1178 Air/Fuel Feedback Max. Air Leakage Adaption P0445 Purge Valve Short to +12V
P1179 Air Fuel Feedback Min. Air Leakage Adaption P0500 Road Speed Sensor Circuit Fault
P0201 Injector 1 Circuit Fault P0505 IACV Stepper Motor/Circuit Fault
P0202 Injector 2 Circuit Fault P0560 System Power Circuit Fault
P1201 Injector 1 Open Circuit/Short to Ground P1560 Sensor Supply Voltage Circuit Fault
P1202 Injector 2 Open Circuit/Short to Ground P0562 Low System Voltage
P1205 Injector 1 Short to +12V P0563 High System Voltage
P1206 Injector 2 Short to +12V P1600 Check Engine Lamp Circuit Fault
P1231 Fuel Pump Open Circuit/Short to Ground P1601 Check Engine Lamp Open Circuit/Short to Gnd
P1232 Fuel Pump Short to +12V P1602 Check Engine Lamp Short to +12V