Kohler 5ECD Service Manual page 31

SECM Fault Codes and Diagnostics (Continued)
Fault
Code
Displayed Description
EC55 Transducer Voltage (XDRP)
Sensor Input Low
EC56* Intake Air Temperature (IAT)
Input Sensor High
EC57* Intake Air Temperature (IAT)
Input Sensor Low
EC58* Engine Coolant
Temperature (ECT) Sensor
Input High
EC59* Engine Coolant
Temperature (ECT) Sensor
Input Low
EC60* Oxygen Sensor Input High
EC61 Oxygen Sensor Input Low
EC62 Seawater Pump Pressure
OS Engine Overspeed Fault
HE Engine Coolant
Temperature (ECT) Sensor
Range High
EC69* O2 Sensor Switching Fault
EC72* CAN Receive Message
Fault
* Indicates a stored fault code.
TP-6391 9/08
Check
Fault appears if the sensor power from the SECM drops below 4.8 VDC. (EC11, EC12, and
EC50 are expected faults when the transducer power is lost).
Measure the transducer power at the TMAP connector with a multimeter:
TMAP Pin 3 +5VDC to TMAP Pin 1 XDCR GND
Verify transducer power at the SECM with a multimeter:
SECM Pin 18 +5VDC to SECM Pin 1 XDCR GND
Verify transducer power at the ETC with a multimeter:
ETC Pin 3 XDCR PWR to ETC Pin 2 XDCR GND
Fault appears if the TMAP temperature signal wire is disconnected or the circuit is open to the
SECM. Check the TMAP connector and IAT signal wiring for an open circuit:
TMAP Pin 2 to SECM Pin 4 (SIGNAL)
TMAP Pin 1 to SECM Pin 1 (GND)
TMAP Pin 3 to SECM Pin 18 (XDCR +5VDC)
To check the IAT sensor of the TMAP, disconnect the TMAP connector and measure the IAT
resistance. See Figure 5-15.
Fault appears if the TMAP temperature signal wire has become shorted to ground, shorted to
the MAP signal, the TMAP has failed or the SECM has failed. Check the TMAP connector and
IAT signal wiring for a shorted circuit:
TMAP Pin 2 to SECM Pin 4 (SIGNAL)
TMAP Pin 1 to SECM Pin 1 (GND)
TMAP Pin 3 to SECM Pin 18 (XDCR +5VDC)
To check the IAT sensor of the TMAP, disconnect the TMAP connector and measure the IAT
resistance. See Figure 5-15.
Fault appears if the coolant sensor wire is disconnected or the circuit is opened to the SECM.
Check if the sensor connector is disconnected or for an open circuit:
SECM (SIGNAL) Pin 16 to ECT Pin A
SECM (GND) Pin 1 to ECT Pin B
Fault appears if the coolant sensor wire is shorted to ground or the sensor has failed. Check
the sensor connector and wiring for a short to GND:
SECM (SIGNAL) Pin 16 to ECT Pin A
SECM (GND) Pin 1 to ECT Pin B
Fault appears if the O2 sensor SECM driver signal is shorted to power. Check if the O2 sensor
is shorted to +5VDC or battery:
O2 (SIGNAL) Pin B to SECM Pin 3
Verify operation of O2 sensor heater circuit by measuring circuit resistance of 2.1 ohms
¦ 0.4 ohms:
O2 Pin C (HEATER GND) to Pin D (HEATER PWR)
Fault appears if the oxygen sensor input is low. Check the O2 sensor connector and wiring for
a short to ground:
ECM (SIGNAL) Pin 3 to O2 Sensor Pin B
ECM (GND) Pin 1 to O2 Sensor Pin A
Fault appears when seawater cooling is lost. Check the seawater strainer for clogged material.
Check the seawater pump impeller. Check if wire 215 is shorted to ground. See Figure 4-5.
Fault appears when the engine RPM increases beyond the max. RPM setpoint. Typically this
occurs with one or more throttle faults. Check for ETC sticking or other ETC faults. See
Figure 4-5.
Fault appears when the sensor has measured an excessive coolant temperature typically due
to engine overheating. Check the coolant system for seawater blockages, proper coolant level,
and any leaks in the coolant system. See Figure 4-5. Check for possible ECT short to GND.
Check the ECT signal wiring:
SECM (SIGNAL) Pin 16 to ECT Pin A
SECM (GND) Pin 1 to ECT Pin B
Fault appears when the O2 sensor can no longer switch or be driven above and below 500mv
by the SECM. O2 Sensor is not switching across the reference AFR voltage. Check for an
open coil by disconnected the connector and measuring the resistance (approx. 26 ohms¦
2 ohms):
Pin A (SIGNAL) to Pin B (PWR)
See Figure 4-7 and Figure 4-8.
Section 4 Controller 31