DTC P1653 Air Conditioning (A/C) Clutch Relay Control Circuit. Oldsmobile Aurora 1996

For 1990-2009 cars only

Makes 🢒 Oldsmobile 🢒 1996 🢒 Aurora 🢒 Engine 🢒 Engine Controls - 4.0L and 4.6L 🢒 DTC P1653 Air Conditioning (A/C) Clutch Relay Control Circuit

Refer to Electrical Schematic Diagrams for wiring views.

Circuit Description

The PCM contains chips called Output Driver Modules that provide 7 switchable ground outputs for operting solenoids, relays, telltales and other devices. Each of these ground outputs has fault lines that feed back to the PCMs microprocessor. When the output is OFF, the output driver should receive the 12 volts fed to the solenoid, relay, etc. When the output is ON the output driver should receive 0 volts since it grounding the output. If it receives 0 volts when the output is OFF or 12 volts when the output is ON, it sets the fault line low. DTC P1653 is used to monitor the fault line of the A/C Compressor Clutch Relay.

Conditions for Running the DTC

•	DTC P1640 is not set.

•	Engine running at least 10 seconds.

Conditions for Setting the DTC

Fault line is low for 2.5 seconds

Action Taken When the DTC Sets

•	The Malfunction Indicator Lamp (MIL) will not illuminate.

•	No message will be displayed.

Conditions for Clearing the DTC

•	A History DTC will clear after forty consecutive warm-up cycles with no failures of any non-emission related diagnostic test.

•	A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail.

•	Use a scan tool to clear DTCs.

•	Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Clearing Diagnostic Trouble Codes in PCM Description and Operation.

Diagnostic Aids

The PCM will energize the A/C clutch whenever the engine is running less than 4700 RPM and A/C has been requested, unless any of the following conditions are met:

•	A/C head pressure greater than 414 psi (2854 kPa) or less than 38 psi (262 kPa) as determined by the A/C refrigerant pressure switches.

•	A/C evaporator temperature less than 2°C (36°F).

•	Engine at wide open throttle.

•	High power steering load.

•	Low ignition voltage.

•	Engine speed greater than 4700 RPM for 6 seconds.

•	ECT greater than 125°C (257°F).

Test Description

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

The Failure Record information that was stored by the PCM when the DTC set may be lost if the PCM connectors are disconnected. This information may be useful if an intermittent condition is present.

Normally, ignition feed voltage should be present on the control circuit with the PCM disconnected and the ignition turned ON.

Checks for a shorted component or a short to B+ on the control circuit. Either condition would result in a measured current of over 500 milliamps. Also checks for a component that is going open while being operated, resulting in a measured current of 0 milliamps.

Checks for a short to voltage on the control circuit.

This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.

Step

Action

Value(s)

Yes

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

Go to Step 2

Go to the A Powertrain On Board Diagnostic (OBD) System Check

Using the scan tool Capture the Info stored when the DTC set (Failure Records).
Turn OFF the ignition switch.
Disconnect the PCM.
Turn ON the ignition switch.
Using a J 39200 Digital Multimeter, measure voltage between the A/C compressor control relay control circuit at the PCM harness connector and ground.

Is voltage near the specified value?

B+

Go to Step 3

Go to Step 6

Disconnect the A/C compressor clutch electrical connector.
Connect the digital multimeter to measure current draw between the A/C compressor control relay control circuit at the PCM harness connector and ground.
Monitor the amperage reading on the digital multimeter for at least 2 minutes.

Does the amperage draw remain between the specified values?

0.05-0.5 Amp

(50-500 mA)

Go to Step 11

Go to Step 4

Turn OFF the ignition switch.
Reconnect the A/C compressor clutch electrical connector.
Disconnect the A/C compressor control relay (leave the PCM disconnected).
Turn ON the ignition switch.
Using the digital multimeter, measure voltage between the A/C compressor control relay control circuit and ground.

Is voltage at the specified value?

0 V

Go to Step 10

Go to Step 5

Locate and repair short to voltage in the A/C compressor control relay control circuit. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Powertrain Control Module Diagnosis for Verify Repair

Turn OFF the ignition switch.
Check the ignition feed fuse for the A/C compressor control relay.

Is the fuse blown?

Go to Step 7

Go to Step 8

Locate and repair short to ground. Refer to Wiring Repairs in Wiring Systems.

•	A shorted A/C Compressor Relay

•	A shorted A/C Compressor Clutch

•	A shorted A/C Compressor Clutch Diode

•	A short to ground on the ignition feed circuit

•	A short to ground on the A/C Compressor Clutch circuit

Replace the fuse.

Is the repair complete?

Go to Powertrain Control Module Diagnosis for Verify Repair

Disconnect the A/C compressor control relay.
Turn ON the ignition switch.
Measure voltage between the ignition feed circuit for the A/C compressor control relay and ground.

Is voltage near the specified value?

B+

Go to Step 9

Go to Step 13

Check the A/C compressor control relay control circuit for an open or a short to ground.
If a problem is found, repair the A/C compressor control relay control circuit. Refer to Wiring Repairs in Wiring Systems.

Was a problem found?

Go to Powertrain Control Module Diagnosis for Verify Repair

Go to Step 10

Check for the following conditions:

•	The A/C compressor control relay control circuit for a poor connection at the PCM.

•	The A/C compressor control relay control circuit for a poor terminal connection at the A/C compressor control relay.

•	The A/C compressor control relay ignition feed circuit for a poor terminal connection at the A/C compressor control relay.

If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found?

Go to Powertrain Control Module Diagnosis for Verify Repair

Go to Step 14

Turn OFF the ignition switch.
Reconnect the A/C compressor clutch electrical connector.
Reconnect the PCM.
Disconnect the A/C compressor control relay.
Turn ON the ignition switch.
Connect a test light between the A/C compressor control relay control circuit and the ignition feed circuit at the A/C compressor control relay harness connector.
Using the scan tool outputs test function, cycle the A/C compressor control relay output ON and OFF. The HVAC A/C selector button may need to be in the ON position.

Does the test light flash ON and OFF?

Fault not present.

Go to Step 12

Check the A/C compressor control relay control circuit for a poor terminal connection at the PCM.
If a problem is found, repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a problem found?

Go to Powertrain Control Module Diagnosis for Verify Repair

Go to Step 15

Locate and repair open in ignition feed circuit to the A/C compressor control relay or the cause of no voltage to the relay fuse. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

Go to Powertrain Control Module Diagnosis for Verify Repair

Replace the A/C compressor control relay.

Is the replacement complete?

Go to Powertrain Control Module Diagnosis for Verify Repair

Replace the PCM.

Refer to PCM Replacement/Programming .

Is the replacement complete?

Go to Powertrain Control Module Diagnosis for Verify Repair