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JD. Engine Falters or Stops With A/C On



JD. The Engine Falters or Stops Running When the Air Conditioning (A/C) is Used

JD1




Adjusting The Throttle Body (TB)
^ Adjusting the TB KA1. KA. Idling Engine Stops Running When Loaded
^ Continue with DTM 2 JD2.

JD2




Diagnostic Test Mode (DTM) 2
- Start the engine.
Go into DTM 2 in accordance with C. Fault tracing via the DLC.
^ Continue with Checking the A/C control JD3.

JD3




Checking The Air Conditioning (A/C) Control
- Disconnect the pressure regulator (pressostat) connector located on the accumulator.
- Switch on the fan.
- Put the A/C control into the on position
The OBD system should respond with the code 1-1-4.

If the response code 1-1-4 is obtained
^ Check the pressure regulator JD7.

If there is no response code
The control module is not receiving a signal from the A/C control when this is put in the on position.
^ Connecting the test box JD4.

JD4




Connecting The Test Box
Connect the test box to MFI and check the connections to GND in accordance with P1-P2. P. Test Box, Signal Description
^ Continue with Checking the A/C control and wiring JD5.

JD5




Checking The Air Conditioning (A/C) Control And Wiring
- Ignition off.
Connect an ohmmeter between #15 and #5 (GND).
The ohmmeter should read approx. 35 ohms when the A/C control is on and infinite resistance when the A/C control is off.

If this value is OK
^ Check the signal from the A/C control JD6.

If the reading is incorrect
^ Check the wiring for breaks and contact resistance in accordance with NA2 and NA6. NA. Checking the Wiring

JD6




Checking The Signal From The Air Conditioning (A/C) Control
- Connect the control module to the test box.
- Install fuse 1 (or 31).
- Start the engine.
- Switch on the fan.
Connect a voltmeter between #15 and #5 (GND).
The voltmeter should read battery voltage when the A/C control is on and approx. 0 V when the A/C control is off.

If this value is OK
Intermittent fault.
^ Check the connections for loose contacts in accordance with NA5. NA. Checking the Wiring

If the reading is incorrect
^ Check the wiring for breaks and contact resistance in accordance with NA2 and NA6. NA. Checking the Wiring

JD7




Checking The Pressure Regulator
- Reconnect the pressure regulator.
The OBD system should respond with the code 1-3-4 when the compressor engages or disengages.

If the response code 1-3-4 is obtained
^ Adjust in accordance with WA. Checking TB adjustment. WA. Checking the Throttle Body (TB) Adjustment

If there Is no response code
The control module is not receiving a signal from the pressure regulator when it engages the compressor.
^ Connect the test box JD8.

JD8




Connecting The Test Box
Connect the test box to MFI and check the connections to GND in accordance with P1-P2. P. Test Box, Signal Description
^ Continue with Checking the wiring to the A/C compressor JD9.

JD9




Checking The Wiring To The Air Conditioning (A/C) Compressor
- Ignition off.
Connect an ohmmeter between #14 and #5 GND.
The ohmmeter should read approx. 3 ohms.

If this value is OK
^ Check the signal from the A/C compressor JD10.

If the reading is incorrect
^ Check the wiring for breaks and contact resistance in accordance with NA2 and NA6. NA. Checking the Wiring

JD10




Checking The Signal From The Air Conditioning (A/C) Compressor
- Connect the control module to the test box.
- Install fuse 1 (or 31).
- Start the engine
- Switch on the fan and switch on A/C.
Connect a voltmeter between #14 and #5 (GND).
The voltmeter should read battery voltage when the A/C compressor is on and approx. 0 V when the A/C compressor is off.

If this value is OK
^ Repeat DTM 2 JD2.

If the reading is incorrect
^ Check the wiring for breaks and contact resistance in accordance with NA2 and NA6. NA. Checking the Wiring