Checking heater plugs
- Make
- Fiat
- Model
- Panda (141) Factory Service Manual
- Year
- 1986–2003
- Section
- Pre-heating (Panda D) › Checking heater plugs
CHECKING HEATER PLUGS
If there are difficulties in starting, take care to ensure that all the heater plugs are operating correctly. The continuity of each plug is checked using a digital type ohmmeter (Ω = 0.6). It is advisable to carry out this check with the heater plugs fitted on the cylinder head, since such a fault in a heater plug may not show up if it is checked out of its mounting as the effects of the fitting pressure no longer come to bear in these conditions.
Also ensure that the engine cut out solenoid on the injection pump is not short circuited or disconnected.
NOTE Also remember that difficulties in starting may be due to excessively worn engine seals, a defective starter motor or a discharged or badly connected battery.
MAIN FAULT DIAGNOSIS FOR PRE-HEATING DEVICE
| Problem | Cause | Remedy |
|---|---|---|
| Heater plugs warning light does not come on | Bulb burnt out Connection between warning light and contact 6 of control unit open |
Replace bulb Renew connection or clean terminals of oxidized cable |
| Control unit faulty | Replace control unit | |
| Engine produces excess smoke during cold starts | Connection between contact 50 of starter motor and contact 4 of control unit open | Renew connection of clean terminals of oxidized cable |
| Difficulties in starting engine | Faulty control unit making pre-heating period too short | Replace control unit |
| Engine won't start | Control unit not connected to earth | Check that contact 6 of the control unit is properly connected to earth |
| One or more of the heater plugs is short circuited internally | Replace the faulty heater plug(s) | |
| Connection between contact 15 of the ignition switch and contact 3 of the control unit broken | Renew connection | |
| Connection between contact 3 of the control unit and the engine cut out solenoid on the injection pump broken | Renew connection or clean the oxidized terminals | |
| Ignition switch faulty | Replace ignition switch |
Parts & tools for this job For 1986 Fiat Panda
- TOOLA/C manifold gauge setSearch: AC manifold gauge set
- TOOLUV leak detection kitSearch: AC UV leak detection kit
- PARTCabin filterSearch: Fiat Panda 1986 cabin filter
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