Electric Cooling Fan Diagnosis. Chevrolet Beretta 1996

For 1990-2009 cars

Refer to

#### Cooling Fan Motor and Cooling Fan Relay

A/C Compressor Clutch, A/C Compressor Clutch Relay, and HAVOC Controland A/C Assembly
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

### Circuit Description

The relay coils are energized when the PCM completes the ground path. The PCM Output Driver Module (ODM) B output 1 is grounded for Fan 1 operation. PCM ODM B output 2 is grounded for Fan 2 operation.

During Fan 1 operation the PCM supplies a ground path for the Fan 1 relay through ODM B Output 1. This closes the relay contacts and current flows through the relay and to the cooling fan. The primary cooling fan is grounded at the engine block.

During Fan 2 operation the PCM keeps Fan 1 energized and supplies a ground path for the Fan 2 relay allowing current flow to Fan 2. Fan 2 is also grounded to the engine block.

### Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table.

1. Stored Diagnostic Trouble Codes (That may not illuminate the Malfunction indicator Lamp) may enable the engine cooling fans. This Diagnostic Table may lead to improper diagnosis and replacement of good parts if Diagnostic Trouble Codes are present.

2. Ambient temperature must be above 9°C 48°F) before the PCM will enable the cooling fans due to A/C request. The PCM will enable the cooling fans if A/C refrigerant pressure increases regardless of ambient temperature.

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | Go to Step 2 | Go to Powertrain OBD System Check
2 | Are any DTC(s) stored? | -- | Go to applicable DTC(s) Table(s) | Go to Step 3

3

1. Engine coolant below 100°C (212).
2. A/C OFF.
3. Ignition ON.

Is Fan 1 ON?

--

Go to Step 4

Go to Step 22

4 | Select scan tool Misc. Tests, Relay Control function and command Fan 1 ON. Is Fan 1 ON? | -- | Refer to Diagnostic Aids | Go to Step 5

5

1. Remove Fan 1 relay.
2. Ignition ON engine OFF.
3. Connect a test light between B+ and cooling fan relay control in relay harness connector.
4. Select scan tool Misc. Test, Relay Control Function and command Fan 1 ON.

Is test light ON?

--

Go to Step 6

Go to Step 14

6 | Check for a blown fuse. Is fuse blown? | -- | Go to Step18 | Go to Step 7

7

1. Connect a test light to ground.
2. Check for B+ in Fan 1 relay harness connector.

Is test light ON?

--

Go to Step 9

Go to Step 8

8 | Locate and repair open battery feed circuit in Fan 1 relay connector. Refer to Repair Procedures in Electrical Diagnosis. Is action complete? | -- | Go to 29 | --

9

1. Ignition OFF.
2. Connect a 20 Amp fused jumper between B+ and cooling fan circuit in the Fan 1 relay connector.
3. Observe Fan 1.

Is Fan 1 running?

--

Go to Step 28

Go to Step 10

10

1. Disconnect the Fan 1 electrical connector.
2. With the 20 Amp fused jumper between B+ and cooling fan circuit in the Fan 1 relay connector, connect a test light between Fan 1 harness connector terminals.

Is the test light ON?

--

Goto step 27

Go to Step 11

11

1. Connect the test light to B+.
2. Probe the Engine Cooling Fan Motor ground circuit at the Fan 1 connector

Is the test light ON?

--

Go to Step 12

Go to Step 13

12 | Locate and repair open in Engine Cooling Fan Motor feed circuit. Refer to Repair Procedures in Electrical Diagnosis. Is action complete? | -- | Go to Step 29 | --
13 | Locate and repair open in the Engine Cooling Fan Motor Ground circuit. Refer to Repair Procedures in Electrical Diagnosis. Is action complete? | -- | Go to Step 29 | --

14

1. Connect a test light to ground.
2. Probe cavity 85 at the Fan 1 relay connector.

Is the test light ON

--

Go to Step 15

Go to Step 16

15

1. Ignition OFF.
2. Disconnect the PCM connector.
3. Connect a test light between Battery feed and Cooling Fan relay control circuits at Fan 1 relay connector.
4. Jumper the Fan 1 relay driver circuit to ground at PCM connector.

Is test light ON?

--

Go to Step 26

Go to Step 17

16 | Locate and repair open in the battery feed circuit to 85 in Fan 1 relay connector. Refer to Repair Procedures in Electrical Diagnosis. Is action complete? | -- | Go to Step 29 | --
17 | Locate and repair open in Fan 1 relay driver circuit. Refer to Repair Procedures in Electrical Diagnosis. Is action complete? | -- | Go to Step 29 | --

18

1. Remove fuse to Cooling Fan relay.
2. Connect a test light to B+.
3. Probe cavity 30 at Fan 1 Relay connector.

Is test light ON?

--

Go to Step 19

Go to Step 20

19 | Locate and repair short to ground in battery feed circuit to cavity 30 in Fan 1 relay connector. Refer to Repair Procedures in Electrical Diagnosis Section 8A. Is action complete? | -- | Go to Step 29 | --

20

1. Disconnect Engine Cooling Fan Motor connector.
2. Connect test light to B+.
3. Probe cavity 87 at Fan 1 relay connector.

Is test light ON?

--

Go to Step 21

Go to Step 27

21 | Locate and repair short to ground in Engine Cooling Fan Motor feed circuit. Refer to Repair Procedures in Electrical Diagnosis. Is action complete? | -- | Go to Step 29 | --
22 | Using scan tool monitor A/C pressure. Does scan tool indicate A/C pressure greater than the specified value? | 190 psi | Go to Step 23 | Go to Step 24

23

1. Disconnect A/C Pressure sensor.
2. Using scan tool monitor A/C pressure.

Is A/C pressure display at the specified value?

0 psi

Go to Step 25

Go to Step 26

24 | Locate and repair short to voltage in Engine Cooling Fan motor feed circuit. Refer to Repair Procedures in Electrical Diagnosis. Is action complete? | -- | Go to Step 29 | --
25 | Replace A/C Pressure sensor. Is action complete? | -- | Go to Step 29 | --
26 | Replace PCM. Important: The replacement PCM must be programmed. Refer to PCM Replacement/Programming. Is action complete? | -- | Go to Step 29 | --
27 | Replace Engine Cooling Fan motor. Is action complete? | -- | Go to Step 29 | --
28 | Replace Fan 1 Relay. Is action complete? | -- | Go to Step 29 | --

29

1. Engine coolant temperature less than 100°C (212°F).
2. A/C select switch OFF.
3. Ignition ON.

Is Engine Cooling Fan OFF?

--

System OK

Go to Step 3