
RENR5622 97
Troubleshooting Section
Table 33
Diagnostic Codes Table
Description
Conditions wh
ich Generate this Code
System Respon
se
MID 0036 - CID 0545 - FMI 05 Ether
Start Relay open/short to +batt
The engine’s Electronic Control Module
(ECM) detects an open circuit and/or a
short circuit to the +Battery terminal at
the output to the ether start relay.
The ECM has been powered for at least
two seconds.
MID 0036 - CID 0545 - FMI 06 Ether
Start Relay short to ground
The ECM detects a short circuit to
ground at the output to the ether start
relay.
The ECM has been powered for at least
two seconds.
The code is logged.
Ether injection is disabled.
MID 0036 - CID 0546 - FMI 05 Ether
Hold Relay open/short to ground
The EC M detects an open circuit and/or
a short circuit to ground at the output to
the ether hold relay.
The ECM has been powered for at least
two seconds.
MID 0036 - CI
D 0546 - FMI 06 Ether
Hold Relay short to +bat t
The ECM dete
cts a short circuit to the
+Battery at the output to the ether hold
relay.
The ECM has
been powered for at least
two seconds.
The code is l
ogged.
Ether injection is disabled.
When the engine is in AUTO mode the engine
uses an ether system to improve starting in cold
temperatures. The duration of the ether cycle is
based on the engine coolant temperature. The
Electronic Control Module (ECM), which controls the
ether system uses the engine coolant temperature
sensor to detect the engine temperature. The
ECM determines if ether should be injected by
monitoring the actual engine rpm and the engine
coolant temperature. The ECM will activate the ether
solenoid if the engine coolant temperature is below
a set temperature and engine rpm is below a certain
level. The ether will activate for a minimum of 15
secondsat30°C(86°F)uptoamaximumof130
seconds at −50 °C (−58 °F). The automatic ether
injection system is disabled whenever the engine rpm
exceeds 400 rpm or the engine coolant temperature
exceeds 30 °C (86 °F).
The ether injection system can also be operated in
manual mode. The ether system is switched into
manual mode whenever the starting aid switch is
depressed. Manual mode also allows ether to be
injected whenever the coolant temperature is less
than 30 °C (86 °F) and the engine rpm is greater
than 50 rpm. Ether is injected in manual mode if
the starting aid switch is depressed and the coolant
temperature is below the maximum limit.
The ether start relay initially energizes the ether
solenoid for approximately two seconds. After two
seconds, the ether hold relay energizes and the
ether start relay de-energizes. The voltage from the
ether hold relay to the ether solenoid is less than
battery voltage because of the voltage drop over the
resistance that is in the resistor and diode assembly.
The initial higher voltage is needed to actuate the
ether solenoid. The lower voltage signal is then used
to hold the ether solenoid valve open. The solenoid
will be damaged if full battery voltage is applied
continuously.
Two circuits from the ECM are used to control the
ether cycle. The device drivers in the first circuit
provide a +Battery voltage to the coil of the ether
start relay and a return path to the ECM from the coil
of the ether start relay. The ECM monitors current
flow at two places in the circuit in order to determine
if there is a problem in the circuit. The ECM monitors
current flow on the device driver to the coil of the
ether start relay and the ECM monitors current flow
on the device driver from the coil of the ether start
relay. If current is below a threshold on either device
driver in the circuit, the ECM will generate a 545-05
diagnostic code. If current is above a threshold
on either device driver in the circuit, the ECM will
generate a 545-06 diagnostic code. If a 545-06
diagnostic code is generated, the ECM will latch both
device drivers open for overcurrent protection.