Climate control working irregularly
- Make
- Fiat
- Model
- Multipla Factory Service Manual
- Year
- 1998–2010
- Section
- Climate control › Climate control working irregularly
Fault diagnosisClimate control working irregularly
CLIMATE CONTROL WORKING IRREGULARLY
The control unit operates the fan which sends air into the passenger compartment normally, with the pre-set flows, but this air sometimes makes the temperature in the passenger compartment too low and sometimes too high.
| Results of the tests | ||||
| 1 | SYSTEM OPERATION CHECK | All OK | Problems met | Operation |
|---|---|---|---|---|
| Check that the system cooling is correct: See Test 5040A Checking operation of air conditioner (temperature) | Continue to Step 2 | The temperature decreases very slowly: insufficient fluid: | Re-pressurize the system: Op. 5040A10 | |
| 2 | SYSTEM PRESSURE CHECK | All OK | Problems met | Operation |
| Check the system pressure: See Test 5040B Check on operation of air conditioning system (pressures) | Continue to Step 3 | High pressure does not increase or low pressure decreases too much: leaks in the circuit | Locate the leaks Op. 5040A14 | |
| High pressure correct, low pressure very high | Replace the expansion valve Op. 5040B30 | |||
| High pressure high, low pressure below normal | Clean or replace the drier filter Op. 5040A44 | |||
| Pressure trends irregular: pipes obstructed | Wash the system, see Op. 5040A10 | |||
| Pressure trends irregular: evaporator obstructed. | Replace the evaporator: Op. 5040C64 | |||
| 3 | CONDENSER CHECK | All OK | Problems met | Operation |
| Visually inspect the condition of the condenser: the heat exchange surface should not be dirty or fouled | Continue to Step 4 | Condenser dirty | Clean the condenser if necessary, replace it: Op. 5040A40 | |
| 4 | CHECKING CORRECT OPERATION | All OK | Problems met | Operation |
| Check that the fault is no longer present | End of diagnosis | Fault persists | Search for the fault starting from another symptom' | |
Parts & tools for this job For 1998 Fiat Multipla
- TOOLA/C manifold gauge setSearch: AC manifold gauge set
- TOOLUV leak detection kitSearch: AC UV leak detection kit
- PARTCabin filterSearch: Fiat Multipla 1998 cabin filter
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