Diagnosis and checks of additional heating

Diagnostics and checks

1. Check the customer's complaint.

2. Visually inspect for any obvious mechanical or electrical damage.

Visual inspection

Mechanical factors	Electrical Factors
• Coolant level • Pipeline for supplying air to the combustion chamber • Outlet pipe	• Fuses. • Wiring harness • Plug connector (s).

3. ELIMINATE any obvious causes of problems found during the visual inspection before performing any further checks. CHECK the system is working properly.

4. If the problem persists after visual inspection, PERFORM fuel-fired auxiliary heater troubleshooting using WDS and REPAIR any problems found, proceeding according to the nature of the problem. CHECK the system is working properly.

5. If there is no fault in memory, REFER to the Symptom Chart and CONTINUE according to the symptom.

Symptom table

State	Possible Causes	Action
• Auxiliary fuel-fired heater does not work	•Fuse (And) •Electrical circuit (And) • Outside temperature sensor • Engine operation relay •Additional heater •Powertrain control module (PCM)	• Go to PINPOINT TEST A