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Fiat Croma Factory Service Manual (2005-2010)22 · Fault diagnosis
22 · Diagnostics

P0606 - control unit failure (microprocessor)

Make
Fiat
Model
Croma Factory Service Manual
Year
2005–2010
Section
Examiner - electronic diesel management › P0606 - control unit failure (microprocessor)
Fault diagnosisP0606 - control unit failure (microprocessor)

P0606 - CONTROL UNIT FAILURE (MICROPROCESSOR)

1.9 JTD 8v, 1.9 JTD 16v, 2.4 JTD 20v

The diagnostic equipment signals: Error P0606 (Control unit broken (microprocessor)).

This error is detected if the control unit recognizes a malfunction in the circuit through an internal logic evaluation.

0PRELIMINARY CHECKSALL OKPROBLEMS ENCOUNTEREDACTION

Select the following system on the diagnostic equipment: Diesel EDC16C39 electronic injection system.

Cancel the errors present and turn the ignition key OFF.

Wait for the engine management control unit to switch off (min. 20 secs.).

The main relay is switched off. If the engine is very hot, the fans remain on after the ignition is switched off. In this case, the control unit switches off automatically 10 secs after the fans are switched off.

Move on to Step 1
1ERROR CHECKALL OKPROBLEMS ENCOUNTEREDACTION

Drive the vehicle in different driving conditions (engine speed and engine load) for a long stretch.

Listen out for any unusual noises and other system irregularities.

At the end of the road test, check that none of the following errors is present using the diagnostic equipment:

  • P0335 - Engine rpm sensor, with detail "signal not valid"
  • P0606 - Control unit broken (microprocessor)
  • P1618 – Control unit broken (HW CY940)
End of diagnosis1. The engine is not running smoothly

1. Proceed as instructed in the

See table D003 ENGINE NOT RUNNING SMOOTHLY / (IRREGULAR OPERATION)

2. The engine is losing power

2. Proceed as instructed in the

See table D004 FRONT/ENGINE COUPLING

3. The engine does not produce maximum performance

3. Proceed as instructed in the

See table D005 ABS COUPLING

4. The engine response is poor

4. Proceed as instructed in the

See table D016 ADDITIONAL DASHBOARD/LEFT FRONT DOOR COUPLING

5. There is engine knock

5. Proceed as instructed in the

See table S003 ENGINE KNOCKING

6. Error P0335 is present

6. Proceed as instructed in the

See Test 1060GI ENGINE SPEED CHECK

7. Error P0606 is present

7. Proceed as instructed in the test

See Test 1060GK CONTROL UNIT SOFTWARE AND HARDWARE CHECK

8. Error P1618 is present

8. Proceed as instructed in the test

See Test 1060GL CHECK ON OPERATION OF ENGINE MANAGEMENT CONTROL UNIT MAIN RELAY

Parts & tools for this job For 2005 Fiat Croma

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