Proheat M80 - Manual (Page 60)

PROHEAT G-I PCM SERVICE MANUAL 4-29
VOLTAGE: Step 2
(5 Flashes)
OVERHEAT Diagnostic Code 4
Indicates that the Temperature Sensor detected an inner heat exchanger
surface temperature of 230°F (110°C) within 60 seconds after entering
Cool Down (Purge).
Troubleshoot the Overheat diagnostic code based on:
1. Lack of coolant, air or flow problems in the coolant system.
Go to page 4-27, Steps 1 and 2.
2. Faulty Temperature Sensor. Go to page 4-31.
3. Faulty G-I PCM Temperature Sensor circuit. Go to page 4-31.
To reset the PROHEAT, switch it off and then on again.
VOLTAGE Diagnostic Code 5
Indicates that the supply voltage to the G-I PCM is outside the operating range.
Operating Range:
• 12 volt PROHEAT – 10 to 15 volts.
• 24 volt PROHEAT – 20 to 30 volts.
Troubleshoot the Voltage diagnostic code based on:
1. Low voltage.
• Voltage supply is below the rated requirement.
• Poor or faulty electrical connections.
• Voltage supply source is OK. Voltage drop due to high amperage load
while the PROHEAT is operating or trying to operate.
2. High voltage.
• Voltage supply is above the rated requirement while the vehicle
engine is running.
High Voltage – Check:
The vehicle charging system. Consult the OEM for service requirements.
Low Voltage – Check:
a) System voltage supply source.
b) Wiring harnesses and connection points.
4.1.5
(4 Flashes)
4.1.6
(5 Flashes)
VOLTAGE: Step 1
(5 Flashes)
CAUTION
Repeatedly resetting the PROHEAT
without resolving the Overheat
diagnostic code will damage the
heat exchanger.