5NP-B3Q3X-07

GROUP
NUMBER
HVAC
Technical Service Bulletin
SUBJECT:
17-HA-002
DATE
MODEL(S)
JUNE, 2017
Multiple Models
EXTERNAL CONTROL VALVE (ECV) EQUIPPED
VARIABLE A/C COMPRESSOR DIAGNOSIS PROCEDURE
This bulletin supersedes TSB 14-HA-001 with the latest updated diagnosis and kit information.
Description: This bulletin provides additional service procedures to assist the diagnosis of vehicles
equipped with variable displacement A/C compressors that features an external control valve (ECV).
Refer to the applicable Shop Manual HVAC section of the vehicle, and then follow the procedures
outlined in this bulletin whenever a vehicle with the following symptom(s) are being diagnosed:
 A/C does not get cold enough.
 The high and/or low sides are showing abnormal system pressure on the manifold gauge or GDS.
 High side pressure should be greater than 130 PSI at idle (896kpa, 9.1kg/cm2) with MAX A/C.
NOTICE
The A/C Compressor Diagnosis Kit applies only for vehicles equipped with an external control
valve for the variable A/C compressor. Refer to next page for connection configuration information.
Part Name
Part Number
A/C Compressor Diagnosis Kit
00305 ACKIT TOOL (Order these tool kits through Bosch at 1-866-539-4248)
Main Connection Harness
1
2 Pin
3 Pin
2 Pin
2
Compressor
ECV
3
Extension
Harness 1
Extension
Harness 2
Extension
Harness 3
Main
Connection
Harness
4
4
Main Connection Harness Component Parts:
① Battery Terminal Connection Leads
② Protection Fuse (10A)
③ ON / OFF toggle switch
④ 2 Pin connector (female) for direct
connection to the compressor or to Extension
Harness 1, 2, and 3 (shown at right)
Extension Harnesses
Connector
Extension Harness 1 for 2 Pin
Extension Harness 2 for 3 Pin
Extension Harness 3 for 2 Pin
Circulate To: General Manager, Service Manager, Parts Manager, Warranty Manager, Service
Advisors, Technicians, Body Shop Manager, Fleet Repair
SUBJECT:
ECV EQUIPPED VARIABLE A/C COMPRESSOR DIAGNOSIS PROCEDURE
Connection Configurations:
Diagnosis Kit
Connection Configuration
External Control Valve
Connector
Comment
For connection to the ECV pigtail
harness of the A/C compressor
2 PIN
Main Connection Harness
(Direct connection to A/C
compressor pigtail harness)
External
Control
Valve
2 PIN
For direct connection to the ECV
(not equipped with pigtail harness)
Main Connection Harness
+
Extension Harness 1
External
Control
Valve
3 PIN
Main Connection Harness
+
Extension Harness 2
For use with ECV and magnetic
clutch equipped A/C compressor
External
Control
Valve
2 PIN
Magnetic
Clutch
For direct connection to the ECV
(not equipped with pigtail harness)
Main Connection Harness
+
Extension Harness 3
External
Control
Valve
NOTICE
Connection configuration and type listed in the chart may be subject to change.
Warranty Information:
Normal warranty applies.
TSB #: 17-HA-002
Page 2 of 7
SUBJECT:
ECV EQUIPPED VARIABLE A/C COMPRESSOR DIAGNOSIS PROCEDURE
DIAGNOSIS PROCEDURE:
I. A/C Performance Test
1. Start the engine, set the blower speed to level 2, and select MAX A/C.
 MAX A/C: A/C ON, Coldest Temperature Setting, Recirculated Air, and engine at idle speed.
2. Check system status related to the HVAC system and A/C compressor using the GDS.
 The system status of all related components should be indicating ON.
 If the GDS is showing the compressor status as OFF, then check the various wiring harness
and connection points from the A/C Heater Control Unit to the A/C compressor.
3. Check the A/C pressure using the GDS.
 If the high side pressure is more than 130 PSI, then the A/C system is operating normally.
o Specification: 130 PSI (896kpa, 9.1kg/cm2)
 FOR CLUTCHLESS VARIABLE A/C COMPRESSORS ONLY: If the high side pressure is
below spec, inspect the limiter of the compressor pulley disc & hub assembly while rotating the
engine.
o If the center bolt is stationary and not rotating with the pulley, then it indicates that the
torque limiter has sheared due to internal binding. Replace the compressor.
o If the center bolt in the pulley is rotating at the same speed as the pulley (indicating a
normally operating torque limiter and the compressor has not seized), then continue the
diagnosis by using the A/C Compressor Diagnosis Kit.
TSB #: 17-HA-002
Page 3 of 7
SUBJECT:
ECV EQUIPPED VARIABLE A/C COMPRESSOR DIAGNOSIS PROCEDURE
II. Diagnosis Kit Connection
1. Disconnect the main vehicle wiring harness from the A/C compressor.
NOTICE
Turn the engine OFF before connecting the A/C
Compressor Diagnosis Kit.
Main wiring harness connector
2. Connect the A/C Compressor Diagnosis Kit to the A/C compressor.
 Compressors equipped with a pigtail harness from the ECV:
o Connect to ECV pigtail harness using the Main Connection Harness of the kit.
 Compressors not equipped with a pigtail harness from the ECV:
o Connect using the applicable Extension Harness to connect directly to the ECV.
NOTICE
Refer to the Connector Configurations chart for the connector configuration and type.
Connection configuration and type listed in the chart may be subject to change.
TSB #: 17-HA-002
Page 4 of 7
SUBJECT:
ECV EQUIPPED VARIABLE A/C COMPRESSOR DIAGNOSIS PROCEDURE
III. ECV Resistance Test
1. Connect the B+ Red and negative Black power lead clips of the diagnosis kit to a DVOM set to Ω.
Multimeter Probe Connection
Switch ON
Switch OFF
2. Turn the diagnosis kit switch to the ON position and check the ECV resistance using the DVOM.
 Normal resistance: 10.1 ~ 11.1Ω when AMB temperature is 77°F.
 Resistance may vary according to the engine compartment temperature.
o Acceptable normal resistance range: (8 Ω ≤ ECV Resistance ≤ 14 Ω).
NOTICE
Replace the External Control Valve (ECV) if the resistance is either less than 8Ω or greater
than 14Ω.
 Refer to the applicable parts catalog for the latest service part number of the ECV.
 Do not replace the entire A/C compressor assembly for this condition.
 An ECV service part may not be available for some models with A/C compressors
manufactured by certain suppliers (such as Denso). Until such service parts become
available, replace the A/C compressor.
3. Repeat the A/C Performance Test (started on page 3) after replacing the ECV.
TSB #: 17-HA-002
Page 5 of 7
SUBJECT:
ECV EQUIPPED VARIABLE A/C COMPRESSOR DIAGNOSIS PROCEDURE
IV. A/C Pressure Test
NOTICE
Before starting Step 1:
 Turn the Engine OFF.
 Confirm that the diagnosis kit switch is in the OFF position.
1. Connect the diagnosis kit to the vehicle battery terminals.
 Connect the Red clip to B+ terminal.
 Connect the Black clip to B- terminal.
2. Start the engine, set the blower speed to level 2, select MAX A/C, and engine at idle speed.
 MAX A/C: A/C ON, Coldest Temperature Setting, and Recirculated Air
3. Turn the diagnosis kit switch to the ON position, and then check A/C pressure.
 Specifications below are normal pressures when the ambient temperature is 77°F.
 Using manifold gauge: Low side 20 ~ 40psi, High side 130 ~ 190psi
 Using GDS: A/C pressure shown should read 130 PSI (896kpa, 9.1kg/cm2) or more.
NOTICE
Do not run the A/C with the diagnosis kit switch in the ON position beyond 30 seconds.
The evaporator core or expansion valve may freeze and alter pressure gauge readings.
4. If the pressure is normal using the diagnosis kit (even though it did not pass “Section I. A/C
Performance Test”):
 Check the various wiring harness and connection points from the A/C Heater Control Unit to
the A/C compressor. Repair any damaged wiring or connections along the wiring harness.
5. If out of specification or erratic pressures are showing on the manifold gauge or the GDS:
 Recharge the refrigerant and perform leak testing if refrigerant level is out of specification.
 Check A/C line for blockage if there are no leaks found.
 Check the radiator cooling fan for proper operation.
 Repeat A/C Pressure Test to verify repair.
6. If the test results lead to out of spec compressor:
 Check the ECV pin for bent or poor contact
condition before replacing the compressor.
 Replace the External Control Valve if no other
faults are found and the compressor is not operational.
 Refer to last bullet point in Page 5 regarding ECV service part availability.
NOTICE
To replace the External Control Valve, it is necessary to evacuate the
A/C system and (if necessary) remove the compressor from the engine.
TSB #: 17-HA-002
Page 6 of 7
SUBJECT:
ECV EQUIPPED VARIABLE A/C COMPRESSOR DIAGNOSIS PROCEDURE
V. Record Results and Finalizing Repair
1. Record the diagnosis results on the repair order.
 Document the measured ECV resistance, pressures, and the recovered refrigerant amount.
2. If a new A/C compressor is being installed, then perform a visual check of the ECV connections.
 ECV connection and ECV pin contact condition
 Repeat “Section I. A/C Performance Test” to verify system performance.
ECV connection check
TSB #: 17-HA-002
Bent pin check
Control valve check
Page 7 of 7