CAUTION: To avoid damage to the EFE heater, use caution when working around the carburetor.
After assembling the heater, check that there are no foreign objects left on it.
It should be checked that the sealing ring and oil seal are installed properly.
When removing or installing the heater, do not pull on the electrical wiring.
Before removal, be sure to disconnect the connector from the secondary engine wiring harness. Disconnect the 2-pin connector near the carburetor.
Measure the resistance between the White and Black contacts of the heater.
If the resistance is infinite, replace the heater; if not, start the engine.
Attention! The coolant temperature must be below 60°C.
Next, measure the voltage between the White(+) and Black(-) terminals on the engine wiring harness.
If there is battery voltage, then see point A), if not, then point B).
A) Warm up the engine to operating temperature until the cooling fan comes on. If there is no voltage after this, the EFE system is normal.
If there is voltage, then you should disconnect the 2-pin connector near the heater relay.
Next, measure the voltage between the Blue(+) and Black(-) terminals on the main engine wiring harness.
If there is no voltage, then the relay should be replaced.
If there is voltage, then you should check the functionality of the EFE system control module.
B) Measure the voltage between the White (+) terminal and ground.
If there is battery voltage, then the break in the Black wire between the heater and point G4 should be repaired.
If there is no voltage, then you should check for a break in the White wire between the heater and the heater relay. If the wire is normal, then you should disconnect the 2-pin connector near the heater relay.
Next, measure the voltage between the White/Red(+) wire and ground.
If there is no voltage, then check fuse #24 (30 A). If the fuse is OK, then repair the break in the White/Red wire between the relay and fuse #24.
If there is battery voltage, then you should disconnect the 2-pin connector near the heater relay.
Next, measure the voltage between the Blue (+) and Black (-) terminals on the main engine wiring harness.
If there is no voltage, then the relay should be replaced.
If there is battery voltage, then you should measure the voltage between the Blue (+) contact and ground.
If there is battery voltage, then you should repair the break in the Black wire between the relay and point G4.
If there is no battery voltage, then you should check for a break in the Blue wire between the relay and the EFE control module. If the wire is normal, then you should turn to checking the functionality of the EFE control module.
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