Fault Code 215: Transmission Air Supply Pressure Sensor
J1939: SA 3 SPN 37 FMI 0, 1, 2, 3, 4, 5, 6, 10, 14, 17, 18, 20, 21, 31
Overview
The Endurant HD transmission is equipped with a Transmission Air Supply Pressure Sensor (TASPS) that monitors the air pressure supplied to the transmission from the vehicle. The TASPS taps into the air supply passage and provides a pressure input to the Transmission Control Module (TCM). The TCM monitors the pressure input to verify the transmission has the proper air pressure to actuate the clutch and shift rails. The TASPS is mounted in the MTM and connected to the TCM at the 74-way Transmission Harness Connector.
The vehicle air supply comes from a dedicated transmission air tank. The primary and secondary air gauges in the cab of the vehicle may not reflect the pressure of the transmission air supply line. The transmission air tank is often isolated from the rest of the vehicle air system with a Pressure Protection Valve and/or Check Valve.
Detection
The TCM monitors the Transmission Air Supply Pressure Sensor. If a system failure is detected, the fault is set Active.
Conditions to Set Fault Code Active
FMI 0 – Data Valid But Above Normal (Most Severe): TASPS reports greater than 145 psi (1000 kPa) for 1 second.
FMI 1 – Data Valid But Below Normal (Most Severe): TASPS reports less than 75 psi (517 kPa) for 1 second and one of the following is true:
- a non-neutral mode is selected
- the vehicle is moving
- the engine has been running for 8 minutes
FMI 2 – Data Erratic:
- MTM Type PS-393: TASPS is out of range less than 5 PSIA (34.5 kPa) or greater than 183 PSIA (1262 kPa) for 5 seconds.
- MTM Type PS-496: TASPS is out of range less than 5 PSIA (34,5 kPa) or greater than 203 PSIA (1400 kPa) for 5 seconds.
FMI 3 – Voltage Above Normal or Shorted High: TASPS circuit shorted to power for 5 seconds.
FMI 4 – Voltage Below Normal or Shorted Low: TASPS circuit shorted to ground for 5 seconds.
FMI 5 – Current Below Normal or Open Circuit: TASPS circuit open or shorted to ground for 5 seconds.
FMI 6 – Current Above Normal or Shorted Circuit: TASPS reference voltage out of range not between 4.75V to 5.25V for 5 seconds.
FMI 10 – Abnormal Rate of Change: TASPS reported rate of change higher than expected in less than 1 second.
- During a shift greater than 29 psi (200 kPa)
- Not during a shift greater than 4 psi (28 kPa)
FMI 14 – Special Instructions: TASPS reported greater than 145 psi (1000 kPa) after five shifts and vehicle brake air tank pressure continuously reports less than 135 psi (931 kPa) for 1 second.
FMI 17 – Data Valid but Below Normal (Least Severe): TASPS reports less than 75 psi (517 kPa) for 2 seconds with the engine off and the transmission in gear.
FMI 18 – Data Valid but Below Normal (Moderately Severe): TASPS reports less than 80 psi (552 kPa) for 2 seconds and one of the following is true:
- a non-neutral mode is selected
- the vehicle is moving
- the engine has been running for 8 minutes
FMI 20 – Data Drifted High: TASPS reported a rate of change higher than expected and remained greater than 145 psi (1000 kPa) and vehicle brake air tank pressure continuously reports less than 135 psi (931 kPa) for 1 second.
FMI 21 – Data Drifted Low: TASPS reported less than 58 psi (400 kPa) and the following is true:
- The vehicle brake air tank pressure reported above 110 psi (758 kPa)
- The transmission system confirmed the clutch can be fully opened (released)
FMI 31 – Condition Exists: The TCM is using the reported air pressure information from other vehicle sources to verify sufficient air pressure is available for normal transmission operation. One or more of the following FMIs may set Active indicating the TASPS reported an issue: 2, 10, 14, 20, 21.
Fallback
FMI 0:
- Urge to Move and Creep Mode prohibited
FMI 1:
- If transmission is in gear:
- Amber warning lamp on (OEM Specific)
- Coast Mode and Neutral Coast prohibited
- Urge to Move and Creep Mode prohibited
- Inertia Brake activation prohibited
- Upshifts prohibited
- Clutch engagements prohibited
- Non-Neutral modes prohibited
- PTO Mode prohibited
- If transmission is not in gear:
- Red stop lamp on (OEM Specific)
- Clutch disengagements prohibited
FMI 3, 4, 5, 6:
- No degraded modes
FMI 17:
- Amber warning lamp on
- No degraded modes
- Engine may not crank
FMI 18:
- Amber warning lamp on (OEM specific)
- Coast Mode and Neutral Coast prohibited
- Urge to Move and Creep Mode prohibited
- Inertia Brake activation prohibited
- Upshifts prohibited
- PTO Mode prohibited
FMI 2, 10, 14, 20, 21, 31:
- TCM is using the vehicle-reported air pressure information to verify sufficient air pressure is available for normal transmission operation.
Conditions to Set Fault Code Inactive
FMI 0: TASPS below 145psi (1000 kPa) for 1 second.
FMI 1: TASPS above 75psi (517 kPa) for 1 second.
FMI 2, 3, 4, 5, 6: TASPS in range for 10 seconds.
FMI 10, 14, 20, 21: Key cycle.
FMI 17: TASPS above 75psi (517 kPa) and transmission in neutral.
FMI 18: TASPS above 80psi (552 kPa) for 1 second.
FMI 31: TASPS has not reported an issue after 20 drive cycles (engine running and vehicle moving).
Possible Causes
FMI 0:
- Vehicle air system
- Air compressor governor cut-out set too high or damaged
- Vehicle service event
- Connected to an auxiliary air supply
- Transmission Air Supply Pressure Sensor
- Damaged
- Internal Failure
FMI 1, 18:
- Vehicle air system
- High system demand during low-speed maneuvering with frequent service brake applications
- Vehicle and/or Trailer air leak(s)
- Air compressor mechanically damaged
- Pressure Protection Valve stuck closed
- Air compressor governor: Mis-adjusted or damaged
- Air Dryer - Purge Valve, Check Valve, Air leaks
Note: If necessary, refer to OEM and/or vehicle air system manufacture regarding system operation and diagnostics.
- Internal transmission
- Air leak
- Transmission Air Supply Pressure Sensor
- Damaged
- Internal Failure
FMI 3, 4, 5, 6:
- Transmission Air Supply Pressure Sensor
- Damaged
- Internal failure
- Transmission Air Supply Pressure Sensor harness
- Wiring shorted to power, shorted to ground or open
- MTM Harness
- Wiring shorted to power, shorted to ground or open
- TCM
- Software issue
- Internal failure
FMI 2, 10, 14, 20, 21, 31:
- Transmission Air Supply Pressure Sensor
- Damaged
- Internal failure
FMI 17:
- Engine shut down with the loss of transmission air supply pressure with the transmission in gear
- Transmission service event
- Transmission assembled in gear
Additional Tools
- Endurant HD Service Manual TRSM0950
- Eaton Breakout Box with 74-Way Eaton Diagnostic Adapter - RR1029TR
- Digital Volt/Ohm Meter (DVOM)
- 0-200 psi (0-1379 kPa) air pressure gauge
- Vehicle air supply line fitting at the transmission is a male O-ring ISO-6149, M18x1.5
Component Identification
 |
1. Transmission Control Module (TCM) Cover 2. Transmission Control Module (TCM) 3. 74-Way Transmission Harness Connector 4. TCM Side of 74-Way Transmission Harness Connector 5. Transmission Control Module (TCM) Seal 6. MTM Air Inlet Port |
Fault Code 215 Troubleshooting
Set vehicle parking brake and chock wheels.
Record the transmission fault codes, FMIs, occurrences, and timestamps from the Service Activity report created during the Diagnostic Procedure.
If Fault Code 215 FMI 0, 1, 2, 10, 14, 18, 20, 21 is Active or Inactive, Go to Step B
If Fault Code 215 FMI 3, 4, 6 is Active or Inactive, Go to Step C
If Fault Code 215 FMI 5 is Active or Inactive, Go to Step B
If Fault Code 215 FMI 17 is Active, connect an auxiliary air supply to the vehicle, air up the vehicle air system to 110-130 PSI (758-896 kPa) and key on. Go to Step V
If Fault Code 215 FMI 17 is Inactive, the transmission air supply pressure is in range and transmission is in neutral. Go to Step V
If Fault Code 215 FMI 31 is Active or Inactive, Go to Step M
Key on with engine off.
Connect ServiceRanger.
Go To “Configuration”.
Select “Advanced”.
Note: If “Advanced” is not indicated, transmission is equipped with MTM Type PS-393. Go to Step 7.
Record “MTM Type” Current Value. Use the table in Step 6 to determine next step based on MTM Type.
Note: MTM part number can also be used to determine MTM Type. Locate MTM part information tag and record MTM Part Number (Item 1) in table. Go to Step 6.
Compare MTM Part Number in table to determine MTM Type.
Based on MTM Type determine next step.
| MTM Part Number if recorded from tag | ||
|---|---|---|
| MTM Part Number | MTM Type | Action |
| A-10000715 | PS-393 | If FMI 0, 1, 2, 10, 14, 18, 20, 21, Go to Step H |
| A-10002594 | ||
| A-10004202 | If FMI 5, Go to Step C | |
| A-10004231 | PS-496 | If FMI 0, 1, 18, Go to Step K |
| A-10004356 | If FMI 2, 10, 14, 20, 21, Go to Step L | |
| A-10004383 | If FMI 5, Go to Step N | |
Key off.
Refer to OEM guidelines and verify operation and maintenance of the vehicle air system.
Inspect the vehicle air system for contamination, moisture, corrosion and/or debris.
If an issue is found with the vehicle air system, refer to OEM guidelines for repair or replacement of the vehicle air system. Go to Step D
If no issue is found with the vehicle air system, Go to Step D
Key off.
Remove the TCM from the MTM with the 20-Way TCM Vehicle Harness Connector and 20-Way TCM Body Harness Connector connected.
Inspect the TCM side of the 74-Way Transmission Harness Connector, verify the connector is free from contamination and corrosion; the terminals are not bent, spread or loose; and there is no damage to the connector body.
Inspect the TCM Seal, verify the seal is properly installed and there is no damage to the seal.
Note: MTM removal and installation requires the transmission to be removed from the vehicle. Reference Endurant HD Service Manual TRSM0950, Transmission Removal Service Procedure.
If contamination or damage is found to the TCM side of the 74-Way Transmission Harness Connector, replace the Transmission Control Module (TCM) and Mechatronic Transmission Module (MTM). Go to Step V
If no contamination or damage is found, Go to Step E
Review the Service Activity Report (SAR) and record the MTM Serial Number.
If the MTM Serial Number is greater than or equal to 12S17137123221. Go to Step F
If the MTM Serial Number is less than or equal to 12S17137123220. Go to Step G
Key off.
Connect the Eaton Breakout Box with 74-Way Eaton Diagnostic Adapter to the TCM side of the 74-Way Transmission Harness Connector.
Measure resistance at the Eaton Breakout Box between Pin 8 and Pin 9. Record reading in table.
Key on.
Measure voltage at the Eaton Breakout Box between Pin 7 and Pin 9. Record reading in table.
Compare reading(s) in table.
If readings are in range, replace the Mechatronic Transmission Module (MTM). Go to Step V
Note: MTM removal and installation requires the transmission to be removed from the vehicle. Reference Endurant HD Service Manual TRSM0950, Transmission Removal Service Procedure.
If readings are out of range, replace Transmission Control Module (TCM). Go to Step V
| Ignition State | Pins | Range | Reading(s) |
|---|---|---|---|
| Key off | 8 to 9 | 3k-9k Ohms | |
| Key on | 7 to 9 | 4.75–5.25 V |
Key off.
Connect the Eaton Breakout Box with 74-Way Eaton Diagnostic Adapter to the TCM side of the 74-Way Transmission Harness Connector.
Measure resistance at the Eaton Breakout Box between Pin 10 and Pin 11. Record reading in table.
Key on.
Measure voltage at the Eaton Breakout Box between Pin 10 and Pin 12. Record reading in table.
Compare reading(s) in table.
If readings are in range, replace the Mechatronic Transmission Module (MTM).Go to Step V
Note: MTM removal and installation requires the transmission to be removed from the vehicle. Reference Endurant HD Service Manual TRSM0950, Transmission Removal Service Procedure.
If readings are out of range, replace Transmission Control Module (TCM). Go to Step V
| Ignition State | Pins | Range | Reading(s) |
|---|---|---|---|
| Key off | 10 to 11 | 3k-9k Ohms | |
| Key on | 10 to 12 | 4.75–5.25 V |
Key on with engine off.
Connect ServiceRanger.
Go To “Data Monitor”.
From the Default Parameter Files, select “Transmission and Vehicle Air Supply Pressure”.
Key on with engine running.
Allow air pressure to build to governor cut-out.
Note: Refer to OEM and/or vehicle air system manufacture regarding governor cut-out specification.
In ServiceRanger, monitor Transmission Parameter 520524 - Line Pressure Feedback and record value in table.
On the Vehicle Dash Display, monitor Primary (1) and Secondary (2) Air Pressure Gauges and record readings in table.
Key off and allow engine to shut down.
Key on with engine off.
Wait 1 minute.
After waiting one minute, in ServiceRanger, monitor Transmission Parameter 520524 - Line Pressure Feedback and record value in table.
On the Vehicle Dash Display, monitor and record Primary (1) and Secondary (2) Air Pressure Gauge readings and record values in table.
Note: The complete vehicle air system consists of air system components on both the tractor and trailer. Although the trailer is not typically included in this confirmation, it may affect overall vehicle air system operation.
Compare reading(s) in table. Based on results, determine next steps.
| Source | Parameter | Range | Reading(s) |
|---|---|---|---|
| Transmission | 520524 | 120-135 PSI (827-930 kPa) | |
| Vehicle - Primary (1) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | ||
| Vehicle - Secondary (2) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | ||
| After waiting one (1) minute | |||
| Transmission | 520524 | 120-135 PSI (827-930 kPa) | |
| Vehicle - Primary (1) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | ||
| Vehicle - Secondary (2) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | ||
| Result | Action | ||
| If Vehicle - Source (Primary and Secondary) readings are out-of-range and/or not within +/- 5 PSI (35kPa) of each other: | Refer to OEM and/or vehicle air system manufacture regarding system operation and diagnostics. Go to Step V | ||
| If Transmission - Source reading is out-of-range and both Vehicle - Source (Primary and Secondary) readings are in-range and within +/- 5 PSI (35 kPa) of each other: | Go to Step I | ||
| If all source readings are in-range, within +/- 5 PSI (35 kPa) of each other and the vehicle air system holds pressure, and Fault Code 215 is Inactive: | No issues are currently detected. Go to Step V | ||
| If FMI 1, 18, suspect vehicle experienced a low air pressure event. Go to Step V | |||
Key off.
Refer to OEM guidelines, exhaust the vehicle air system.
Refer to OEM guidelines, exhaust the vehicle air system supply line to the transmission.
Refer to OEM guidelines and remove the vehicle air supply line at the MTM inlet.
Install a 0-200 PSI (1379 kPa) air pressure gauge at the vehicle air system supply line to the transmission.
Key on with engine running.
Allow air pressure to build to governor cut-out.
Key on with engine off.
Key off and allow engine to shut down.
Monitor air pressure gauge at the vehicle air supply line and record reading in table.
Wait one minute.
After waiting one minute, monitor air pressure gauge at the vehicle air supply line and record reading in table.
Compare reading(s) in table.
If readings are out-of-range or vehicle air system does not hold pressure, refer to OEM and/or vehicle air system manufacture regarding system operation and diagnostics. Go to Step V
If readings are in-range and vehicle air system holds pressure, Go to Step J
Note: Refer to OEM and/or vehicle air system manufacture regarding governor cut-out specification.
| Source | Range | Reading(s) |
|---|---|---|
| Air pressure gauge | 120-135 PSI (827-930 kPa) | |
| After Waiting One (1) Minute | ||
| Air pressure gauge | 120-135 PSI (827-930 kPa) | |
Key off.
Continuously depress and release the brake pedal to completely exhaust/empty vehicle air system.
Key on with engine off.
On the Vehicle Dash Display, monitor Primary (1) and Secondary (2) Air Pressure Gauges and record readings in table.
On the pressure gauge connected to the vehicle air supply line to the transmission, monitor air pressure gauge and record reading in table.
Compare reading(s) in table. Based on results, determine next steps.
| Source | Range | Readings |
|---|---|---|
| Vehicle - Primary (1) Air Pressure Gauge | 0 PSI (0 kPa) | |
| Vehicle - Secondary (2) Air Pressure Gauge | 0 PSI (0 kPa) | |
| Vehicle air supply line Pressure Gauge | 120-135 PSI (827-930 kPa) | |
| Results | Action | |
| If Primary or Secondary Gauges indicate 0 PSI and vehicle air supply line to the transmission pressure gauge indicates 0 PSI: | Refer to OEM and/or vehicle air system manufacture regarding system operation and diagnostics. | |
| If Primary and Secondary Gauges indicate 0 PSI and vehicle air supply line to the transmission pressure gauge indicates 120-135 PSI (827-930 kPa): | Contact Eaton Cummins Automated Transmission Technologies for further diagnostic instructions. Go to Contact Information. Go to Step V | |
Key on with engine off.
Connect ServiceRanger.
Go To “Data Monitor”
From the Default Parameter Files, select “Transmission and Vehicle Air Supply Pressure”.
Key on with engine running.
Allow air pressure to build to governor cut-out.
Note: Refer to OEM and/or vehicle air system manufacture regarding governor cut-out specification.
In ServiceRanger, monitor Transmission Parameter 520524 - Line Pressure Feedback and record value in table.
On the Vehicle Dash Display, monitor Primary (1) and Secondary (2) Air Pressure Gauges and record readings in table.
Key off and allow engine to shut down.
Key on with engine off.
Wait one minute.
After waiting one minute, in ServiceRanger, monitor Transmission Parameter 520524 - Line Pressure Feedback and record value in table.
On the Vehicle Dash Display, monitor Primary (1) and Secondary (2) Air Pressure Gauges and record readings in table.
Note: The complete vehicle air system consists of air system components on both the tractor and trailer. Although the trailer is not typically included in this confirmation, it may affect overall vehicle air system operation.
Compare reading(s) in table. Based on results, determine next steps.
| Source | Parameter | Range | Reading(s) |
|---|---|---|---|
| Transmission | 520524 | 120-135 PSI (827-930 kPa) | |
| Vehicle - Primary (1) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | ||
| Vehicle - Secondary (2) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | ||
| After waiting one (1) minute | |||
| Transmission | 520524 | 120-135 PSI (827-930 kPa) | |
| Vehicle - Primary (1) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | ||
| Vehicle - Secondary (2) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | ||
| Result | Action | ||
| If Transmission - Source readings are out-of-range or erratic and Vehicle - Source (Primary and Secondary) readings are in-range and constant: | Go to Procedure E of information bulletin TAIB-1015 Fault Code 215 Transmission Air Supply Pressure Sensor (TASPS) located in TRIB-0900: Endurant Family Transmission Information Bulletin Book. | ||
| If Vehicle - Source (Primary and Secondary) readings are out-of-range and/or not within +/- 5 PSI (35 kPa) of each other: | Refer to OEM and/or vehicle air system manufacture regarding system operation and diagnostics. Go to Step V | ||
| If all source readings are in-range, within +/- 5 PSI (35 kPa) of each other and the vehicle air system hold pressure, and Fault Code 215 is Inactive: | No issues are currently detected. Suspect vehicle experienced a low (FMI 1, 18) or high (FMI 0) air pressure event. Go to Step V | ||
| If an intermittent TASPS issue is suspected, contact Eaton Cummins Automated Transmission Technologies for further diagnostic instructions. Go to Contact Information. Go to Step V | |||
Key on with engine off.
Connect ServiceRanger.
Go To Programming.
Under Software Information, record TCM software part number.
If TCM software part number is equal to or greater than 5541099 (PACCAR TX-12, TX-18) or 5541100 (Endurant HD, XD), Go to Step M
If TCM software part number is less than 5541099 (PACCAR TX-12, TX-18) or 5541100 (Endurant HD, XD), go to Procedure E of information bulletin TAIB-1015 Fault Code 215 Transmission Air Supply Pressure Sensor (TASPS) located in TRIB-0900: Endurant Family Transmission Information Bulletin Book.
Key on with engine running.
Allow air pressure to build to governor cut-out
Note: Refer to OEM and/or vehicle air system manufacture regarding governor cut-out specification.
On the Vehicle Dash Display, monitor Primary (1) and Secondary (2) Air Pressure Gauges and record readings in table.
Key off and allow engine to shut down.
Key on with engine off.
Wait one minute.
After waiting one minute, on the Vehicle Dash Display, monitor Primary (1) and Secondary (2) Air Pressure Gauges and record readings in table.
Note: Fault Code 215 FMI 2, 10, 14, 20, 21, and/or 31 indicates the TCM is using the reported air pressure information from other vehicle sources to verify sufficient air supply pressure is available for normal transmission operation.
Compare reading(s) in table. Based on results, determine next steps.
| Source | Range | Readings |
|---|---|---|
| Vehicle - Primary (1) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | |
| Vehicle - Secondary (2) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | |
| After waiting one (1) minute | ||
| Vehicle - Primary (1) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | |
| Vehicle - Secondary (2) Air Pressure Gauge | 120-135 PSI (827-930 kPa) | |
| Result | Action | |
| If Vehicle - Source (Primary and Secondary) readings are out-of-range and/or not within +/- 5 PSI (35 kPa) of each other: | Refer to OEM and/or vehicle air system manufacture regarding system operation and diagnostics. Go to Step V | |
| If vehicle - Source (Primary and Secondary) readings are in-range, within +/- 5 PSI (35 kPa) of each other and the vehicle air system holds pressure, and the driver is not reporting any of the following: Transmission service lamp, Transmission low air pressure message or Transmission performance issue | No further action required. | |
| If Vehicle - Source (Primary and Secondary) readings are in-range, within +/- 5 PSI (35 kPa) of each other and the vehicle air sustem holds pressure, and the driver is reporting any of the following: Transmission service lamp, transmission low air pressure message or Transmission performance issue | Go to RRMT-0055: Transmission Air Supply Pressure Sensor (TASPS) Replacement Service Procedure - Endurant HD, XD and PACCAR TX-12, TX-18. | |
Key off.
Remove MTM Cover.
Note: Refer to Endurant HD Service Manual TRSM0950 TASPS Service Procedure.
Inspect 3-Way TASPS Connector. Confirm the connector is not damaged, and properly seated and securely latched to the sensor.
Inspect 3-Way TASPS connector wires and harness. Confirm the wires and harness are not damaged or chafed, and that the wire terminals are properly seated and securely locked into the connector.
If a fault is found, record findings with pictures and Contact Eaton Cummins Automated Transmission Technologies for further diagnostic instructions. Go to Contact Information. Go to Step V
If no fault is found, replace TASPS. Go to Step V
Note: Refer to Endurant HD Service Manual TRSM0950 TASPS Service Procedure.
Key off.
Reconnect all connectors and verify that all components are properly installed.
Key on with engine off.
Connect ServiceRanger.
Go to “Fault Codes”.
Select “Clear All Faults”.
Operate vehicle and attempt to reset the fault code or duplicate the previous complaint.
Check for fault codes using ServiceRanger.
If no fault codes set and the vehicle operates properly, test complete.
If Fault Code 215 sets Active during operation, Go to Step A
If a fault code other than 215 sets Active, troubleshoot per Fault Code Isolation Procedure Index.