NHTSA ID Number: 10197651
Manufacturer Communication Number: A21-055
Summary
Service Bulletin – The vehicle’s factory security system will sound off intermittently when the vehicle is parked, and the system is armed.
A21-055
June 11, 2021
Version 1
2017–19 Ridgeline: Alarm Goes Off Intermittently
AFFECTED VEHICLES
| Year | Model | Trim | VIN Range |
| 2017–19 | Ridgeline | ALL | ALL |
SYMPTOM
The vehicle’s factory security system will sound off intermittently when the vehicle is parked, and the system is armed.
POSSIBLE CAUSE
An internal failure within the Keyless Access/TPMS Control Unit.
CORRECTIVE ACTION
Inspect the Alarm Trigger History with i-HDS and replace the Keyless Access/TPMS Control Unit if Ignition Switch (IG1) is listed under the Alarm Device.
PARTS INFORMATION
| Part Name | Trim | Part Number | Quantity |
| Control Unit | RT (2WD and AWD) | 38320-T6Z-A11 | 1 |
| Control Unit | RLT, RTS, and SPORT (2WD and AWD) | 38320-T6Z-A21 | 1 |
| Control Unit | BLACK RTL (-E), and RTL (T 2WD and AWD-NAV/SUN), RTL (T 2WD and AWD – NAVI) | 38320-T6Z-A31 | 1 |
INSPECTION PROCEDURE
1. Connect to the vehicle using the i-HDS.
2. Go to the Body Electrical menu and select Security.
3. Select History Data.
4. If under the Alarm Device column, you see that Ignition Switch (IG1) is listed, proceed to the repair procedure. If is not listed, this bulletin does not apply, proceed with normal troubleshooting.
REPAIR PROCEDURE
NOTE: Before beginning work, all of the vehicle’s keys will need to be available to complete the Keyless Access Control Unit Registration.
1. Remove the passenger’s side dashboard lid.
2. Remove the passenger’s dashboard undercover, then disconnect the connector (for some models).
3. Remove the passenger’s dashboard trim panel.
4. Open the glove box. Release both glove box stops by pushing them in passed the guide stop, then pull down the glove box.
5. Remove the screws.
NOTE: If the screw threads are stripped, replace them with one-size larger (90140-TG7-A00).
6. Remove the glove box, then remove the glove box light and the connector.
7. Release the retaining clip, then remove the Keyless Access/TPMS control unit from the bracket and disconnect the connectors.
8. Install the replacement Keyless Access/TPMS Control Unit.
9. Install all remaining parts in the reverse order of removal.
10. Register the Keyless Access/TPMS control unit using the i-HDS Immobilizer Setup Tool. Follow the instructions when prompted by i-HDS.
NOTE:
- Make sure the 12-volt battery is fully charged before starting registration.
- Connect a fully charged jumper battery to the vehicle, and leave it connected during the entire procedure to maintain steady voltage.
11. Click through to show all the Registration Menu options. Select Replace PCU/BACK UP CONTROLLER/KEYLESS ACCESS Control Unit. Follow the instructions when prompted by i-HDS.
12. After registration, verify all remote related systems work normally with all remotes.
13. Perform the Tire Pressure Sensor ID with i-HDS by following the screen prompts.
14. Select Sensor ID Learning, then follow the instructions when prompted by i-HDS.
NOTE: After the sensor IDs are memorized, reduce the pressure in all four tires to less than the appropriate specification, and check to see that the four tire indicators come on. Clear any DTCs that may have stored while performing this check.
END
3 Affected Products
Vehicle
| MAKE | MODEL | YEAR |
| HONDA | RIDGELINE | 2017-2019 |
1 Associated Document
Manufacturer Communications
A21-055
June 11, 2021
Version 1
MC-10197651-0001.pdf 976.313KB
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SEOCONTENT-START
CUSTOMER INFORMATION: The information in this bulletin is intended for use only by skilled technicians who have the proper tools, equipment,
and training to correctly and safely maintain your vehicle. These procedures should not be attempted by “do-it-yourselfers,” and you should not
assume this bulletin applies to your vehicle, or that your vehicle has the condition described. To determine whether this information applies, contact
an authorized Honda automobile dealer.
© 2021 American Honda Motor Co., Inc. – All Rights Reserved Page 1 of 10
Service Bulletin
21-055
June 11, 2021 Version 1
2017–19 Ridgeline: Alarm Goes Off Intermittently
AFFECTED VEHICLES
Year
Model
Trim
VIN Range
2017–19
Ridgeline
ALL
ALL
SYMPTOM
The vehicle’s factory security system will sound off intermittently when the vehicle is parked, and the system is armed.
POSSIBLE CAUSE
An internal failure within the Keyless Access/TPMS Control Unit.
CORRECTIVE ACTION
Inspect the Alarm Trigger History with i-HDS and replace the Keyless Access/TPMS Control Unit if Ignition Switch (IG1) is listed under the Alarm Device.
PARTS INFORMATION
Part Name
Trim
Part Number
Quantity
Control Unit
RT (2WD and AWD)
38320-T6Z-A11
1
Control Unit
RLT, RTS, and SPORT (2WD and AWD)
38320-T6Z-A21
1
Control Unit
BLACK RTL (-E), and RTL (T 2WD and AWD-NAV/SUN), RTL (T 2WD and AWD – NAVI)
38320-T6Z-A31
1
Page 2 of 10
WARRANTY CLAIM INFORMATION
The normal warranty applies.
Operation Number
Description
Flat Rate Time
Defect Code
Symptom Code
Template ID
Failed Part Number
0505A0
Inspect the Security System with the i-HDS.
0.3 hr.
03124
03217
A21055A
38320-T6Z-A11
A
RT 2WD/AWD – Replace the Keyless Access/TPMS control unit (includes re-programing all keys and TPMS sensor learn/tire check).
0.8 hr.
RTL 2WD/AWD, RTS 2WD/AWD, Sport 2WD/AWD – Replace the Keyless Access/TPMS control unit (includes re-programing all keys and TPMS sensor learn/tire check).
0.8 hr.
A21055B
BLACK RTL (-E), RTL (T 2WD/AWD-NAV/SUN), RTL (T 2WD/AWD – NAVI) – Replace the Keyless Access/TPMS control unit (includes re-programing all keys and TPMS sensor learn/tire check).
0.8 hr.
A21055C
Skill Level: Repair Technician
Page 3 of 10
INSPECTION PROCEDURE
1. Connect to the vehicle using the i-HDS.
2. Go to the Body Electrical menu and select Security.
Page 4 of 10
3. Select History Data.
4. If under the Alarm Device column, you see that Ignition Switch (IG1) is listed, proceed to the repair procedure. If is not listed, this bulletin does not apply, proceed with normal troubleshooting.
Page 5 of 10
REPAIR PROCEDURE
NOTE: Before beginning work, all of the vehicle’s keys will need to be available to complete the Keyless Access Control Unit Registration.
1. Remove the passenger’s side dashboard lid.
2. Remove the passenger’s dashboard undercover, then disconnect the connector (for some models).
Page 6 of 10
3. Remove the passenger’s dashboard trim panel.
4. Open the glove box. Release both glove box stops by pushing them in passed the guide stop, then pull down the glove box.
Page 7 of 10
5. Remove the screws.
NOTE: If the screw threads are stripped, replace them with one-size larger (90140-TG7-A00).
6. Remove the glove box, then remove the glove box light and the connector.
Page 8 of 10
7. Release the retaining clip, then remove the Keyless Access/TPMS control unit from the bracket and disconnect the connectors.
8. Install the replacement Keyless Access/TPMS Control Unit.
9. Install all remaining parts in the reverse order of removal.
Page 9 of 10
10. Register the Keyless Access/TPMS control unit using the i-HDS Immobilizer Setup Tool. Follow the instructions when prompted by i-HDS.
NOTE:
• Make sure the 12-volt battery is fully charged before starting registration.
• Connect a fully charged jumper battery to the vehicle, and leave it connected during the entire procedure to maintain steady voltage.
11. Click through to show all the Registration Menu options. Select Replace PCU/BACK UP CONTROLLER/KEYLESS ACCESS Control Unit. Follow the instructions when prompted by i-HDS.
Page 10 of 10
12. After registration, verify all remote related systems work normally with all remotes.
13. Perform the Tire Pressure Sensor ID with i-HDS by following the screen prompts.
14. Select Sensor ID Learning, then follow the instructions when prompted by i-HDS.
NOTE: After the sensor IDs are memorized, reduce the pressure in all four tires to less than the appropriate specification, and check to see that the four tire indicators come on. Clear any DTCs that may have stored while performing this check.
END
SEOCONTENT-END
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