| Last Modified: 11-29-2007 | 1.6 J | |
| Service Category: Vehicle Interior | Section: Heating/Air Conditioning | |
| Model Year: 2008 | Model: Sequoia | Doc ID: RM000002VXQ004X |
| Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: DESCRIPTION (2008 Sequoia) | ||
|
Air Conditioning Compressor Magnetic Clutch Circuit |
DESCRIPTION
When the air conditioning amplifier is turned on, a magnetic clutch ON signal is sent from the MGC terminal of the air conditioning amplifier. Then, the magnetic clutch relay (MG CLT) turns on to operate the magnetic clutch.
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
|
1. |
CHECK CAN COMMUNICATION SYSTEM |
(a) Connect the Techstream to DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Select "Communication Bus Check"
OK:
All ECUs and sensors connected to the CAN communication system are displayed.
|
|
2. |
READ VALUE USING TECHSTREAM (A/C SIGNAL) |
(a) Connect the Techstream to DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Data List / A/C Signal
(e) According to the display on the Techstream, read the Data List.
ECM
|
Tester Display |
Measurement Item/Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|
|
A/C Signal |
Air conditioning switch signal / ON or OFF |
ON: Air conditioning ON OFF: Air conditioning OFF |
- |
OK:
The display is as specified in the normal condition.
|
|
3. |
INSPECT FUSE (A/C IG) |
|
(a) Remove the A/C IG fuse from the main body ECU. |
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
A/C IG fuse |
Always |
Below 1 Ω |
(c) Reinstall the A/C IG fuse.
|
|
4. |
INSPECT MAGNETIC CLUTCH RELAY (MG CLT) |
(a) Remove the magnetic clutch relay from the engine room relay block.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
3 - 5 |
When battery voltage is not applied between terminals |
10 kΩ or higher |
|
When battery voltage is applied to terminals 1 and 2 |
Below 1 Ω |
(c) Reinstall e the magnetic clutch relay.
|
|
5. |
CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - BATTERY) |
(a) Disconnect the H24 air conditioning amplifier connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
H24-20 (MGC) - Body ground |
Ignition switch off |
Below 1 V |
|
Ignition switch ON |
11 to 14 V |
|
|
6. |
CHECK AIR CONDITIONING AMPLIFIER (MGC VOLTAGE) |
(a) Reconnect the H24 air conditioning amplifier connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
H24-20 (MGC) - Body ground |
Engine running and air conditioning switch ON |
Below 1 V |
|
Engine running and air conditioning switch OFF |
11 to 14 V |
|
|
7. |
INSPECT AIR CONDITIONING COMPRESSOR (COMPRESSOR HARNESS) |
(a) Disconnect the D39 air conditioning compressor connector.
(b) Disconnect the magnetic clutch connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
3 (MG+) - 1 |
Always |
Below 1 Ω |
|
3 (MG+) - Body ground |
Always |
10 kΩ or higher |
|
|
8. |
INSPECT MAGNETIC CLUTCH |
|
(a) Measure the resistance according to the value(s) in the table below. Standard Resistance:
|
(b) When connector terminal 1 is connected to the positive (+) battery terminal, check that the following occurs: 1) the magnetic clutch operating sound can be heard, and 2) the magnetic clutch hub and rotor lock.
Result
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (for 2UZ-FE) |
B |
|
NG (for 3UR-FE) |
C |
(c) Reconnect the air conditioning compressor connector.
(d) Reconnect the magnetic clutch connector.
|
|
9. |
CHECK HARNESS AND CONNECTOR (AIR CONDITIONING COMPRESSOR - ENGINE ROOM RELAY BLOCK) |
(a) Disconnect the D39 air conditioning compressor connector.
(b) Remove the magnetic clutch relay (MG CLT) from the engine room relay block.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
D39-3 (MG+) - Engine room relay block magnetic clutch relay terminal 3 |
Always |
Below 1 Ω |
|
D39-3 (MG+) or Engine room relay block magnetic clutch relay terminal 3 - Body ground |
Always |
10 kΩ or higher |
(d) Reinstall the magnetic clutch relay (MG CLT).
(e) Reconnect the air conditioning compressor connector.
|
|
10. |
CHECK HARNESS AND CONNECTOR (ENGINE ROOM RELAY BLOCK - BATTERY) |
(a) Remove the magnetic clutch relay (MG CLT) from the engine room relay block.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
Engine room relay block magnetic clutch relay terminal 5 - Body ground |
Always |
11 to 14 V |
(c) Reinstall the magnetic clutch relay.
|
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