This is the multi-page printable view of this section. Click here to print.
NTC Overview
NTC 0x0AA.0 LOA Rapid Shutdown
Description:
SF049A Loss of Assist Manager tries to avoid system shutdown when safe sensor redundancy is still in tact. However, in the event that conditions do not allow continued operation, it is LoaMgr’s responsibility to request system shutdown.
Diagnostic Overview:
LoaMgr includes many calibrations used to determine correct system response. Some of them can be given values to intentionally trigger this fault. LoaMgr reacts instantly because all debounce operations are assumed to happen in outside functions that feed intputs to LoaMgr.
Typical Fault Response: F3 Notification Only
The diagnostic is set to an F1. The fault is intended to produce immediate shutdown of the system.
Probable Sources (Most to Least Probable):
•One of LoaMgr’s “Independent Signals” inputs has a runtime value that matches up with one of the “Response” calibrations whose cal value is set to 5.
• One of LoaMgr’s “Independent Signals” inputs is receiving an initial value has a value that matches up with one of the “Response” calibrations whose cal value is set to 5.
•Two or more issues exist in the system simultaneously, which automatically promotes LoaMgr response from calibrated values to a hardcoded response of 5 (Rapid Shutdown Requested). Example: System was already using TLOA due to lost handwheel torque signals, and then the system loses motor current signals. Each response (HwTq and MotCurr) by itself might be cal’d to engage software-based mitigation (TLOA and Voltage Mode), but together they are deemed an illegal combination. Illegal combinations result in F1 shutdown.
Initialization | |
Periodic | |
Event | X |
Date | Revision | Initials |
3/27/2015 | Initial Release | Kevin Derry |
Description of Unusual Event setting NTC | Root Cause / Explanation |
Date | FDD & Rev | Modifications to Diagnostic Function |
3/27/2015 | SF049A v1.0.0 | Initial Implementation |
Algorithm Changes / Lessons Learned / Revision Log
NTC Overview
NTC 0x0AB.0 LOA Controlled Shutdown
Description:
SF049A Loss of Assist Manager tries to avoid system shutdown when safe sensor redundancy is still in tact. However, in the event that conditions do not allow continued operation, it is LoaMgr’s responsibility to request system shutdown.
Diagnostic Overview:
LoaMgr includes many calibrations used to determine correct system response. Some of them can be given values to intentionally trigger this fault. LoaMgr reacts instantly because all debounce operations are assumed to happen in outside functions that feed intputs to LoaMgr.
Typical Fault Response: F3 Notification Only
The diagnostic is set to an F2. The fault is intended to produce shutdown of the system and apply damping to control handwheel kick.
Probable Sources (Most to Least Probable):
•One of LoaMgr’s “Independent Signals” inputs has a runtime value that matches up with one of the “Response” calibrations whose cal value is set to 4.
• One of LoaMgr’s “Independent Signals” inputs is receiving an initial value has a value that matches up with one of the “Response” calibrations whose cal value is set to 4.
Initialization | |
Periodic | |
Event | X |
Date | Revision | Initials |
3/27/2015 | Initial Release | Kevin Derry |
Description of Unusual Event setting NTC | Root Cause / Explanation |
Date | FDD & Rev | Modifications to Diagnostic Function |
3/27/2015 | SF049A v1.0.0 | Initial Implementation |
Algorithm Changes / Lessons Learned / Revision Log
NTC Overview
NTC 0x0AC.0 Handwheel Torque Independent Signals Too Low
Description:
SF049A Loss of Assist Manager tries to avoid system shutdown when safe sensor redundancy is still in tact. However, customers want to prevent EPS from operating when issues occur repeatedly across ignition cycles. Nexteer’s strategy is to provide NTCs for each issue to be tracked.
Diagnostic Overview:
Input signal HwTqIdptSig_Cnt_u08 represents the currently active number of Handwheel Torque signals. When the number of independent signals is equal to or less than a calibration in LoaMgr, the fault status is set instantly to Failed. LoaMgr can react instantly because the function providing the input signal is expected to debounce before dropping to a lower value.
Typical Fault Response: F3 Notification Only
The diagnostic is set to an F3. The fault is intended to produce not immediate change in system behavior. Its purpose is to allow disabling of EPS at the beginning of the Nth ignition cycle.
Probable Sources (Most to Least Probable):
•An individual handwheel torque sensor is offline, due to being out of range or perhaps a protocol issue. This should result in an upstream F3 in an ES function.
•A pair or more of sensors do not correlate with one another. This should result in an additional F3 fault from the upstream ES function: Handwheel Torque Correlation.
Initialization | |
Periodic | |
Event | X |
Date | Revision | Initials |
3/27/2015 | Initial Release | Kevin Derry |
Description of Unusual Event setting NTC | Root Cause / Explanation |
Date | FDD & Rev | Modifications to Diagnostic Function |
3/27/2015 | SF049A v1.0.0 | Initial Implementation |
Algorithm Changes / Lessons Learned / Revision Log
NTC Overview
NTC 0x0AD.0 Motor Angle Independent Signals Too Low
Description:
SF049A Loss of Assist Manager tries to avoid system shutdown when safe sensor redundancy is still in tact. However, customers want to prevent EPS from operating when issues occur repeatedly across ignition cycles. Nexteer’s strategy is to provide NTCs for each issue to be tracked.
Diagnostic Overview:
Input signal MtrPosIdptSig_Cnt_u08 represents the currently active number of Motor Position signals. When the number of independent signals is equal to or less than a calibration in LoaMgr, the fault status is set instantly to Failed. LoaMgr can react instantly because the function providing the input signal is expected to debounce before dropping to a lower value.
Typical Fault Response: F3 Notification Only
The diagnostic is set to an F3. The fault is intended to produce not immediate change in system behavior. Its purpose is to allow disabling of EPS at the beginning of the Nth ignition cycle.
Probable Sources (Most to Least Probable):
•An individual motor position sensor is offline. This should result in an upstream F3 in an ES function.
•A pair or more of sensors do not correlate with one another. This should result in an additional F3 fault from the upstream ES function: Motor Angle Correlation.
Initialization | |
Periodic | |
Event | X |
Date | Revision | Initials |
3/27/2015 | Initial Release | Kevin Derry |
Description of Unusual Event setting NTC | Root Cause / Explanation |
Date | FDD & Rev | Modifications to Diagnostic Function |
3/27/2015 | SF049A v1.0.0 | Initial Implementation |
Algorithm Changes / Lessons Learned / Revision Log
NTC Overview
NTC 0x0AE.0 Motor Current Independent Signals Too Low
Description:
SF049A Loss of Assist Manager tries to avoid system shutdown when safe sensor redundancy is still in tact. However, customers want to prevent EPS from operating when issues occur repeatedly across ignition cycles. Nexteer’s strategy is to provide NTCs for each issue to be tracked.
Diagnostic Overview:
Input signal MotCurrIdptSig_Cnt_u08 represents the currently active number of Motor Current signals. When the number of independent signals is equal to or less than a calibration in LoaMgr, the fault status is set instantly to Failed. LoaMgr can react instantly because the function providing the input signal is expected to debounce before dropping to a lower value.
Typical Fault Response: F3 Notification Only
The diagnostic is set to an F3. The fault is intended to produce not immediate change in system behavior. Its purpose is to allow disabling of EPS at the beginning of the Nth ignition cycle.
Probable Sources (Most to Least Probable):
•For EA3 single-inverter applications, the input signal is coming from SF031A Current Reasonableness.
Initialization | |
Periodic | |
Event | X |
Date | Revision | Initials |
3/27/2015 | Initial Release | Kevin Derry |
Description of Unusual Event setting NTC | Root Cause / Explanation |
Date | FDD & Rev | Modifications to Diagnostic Function |
3/27/2015 | SF049A v1.0.0 | Initial Implementation |
Algorithm Changes / Lessons Learned / Revision Log
NTC Overview
NTC 0x0AF.0 Inverter Independent Signals Too Low
Description:
SF049A Loss of Assist Manager tries to avoid system shutdown when safe sensor redundancy is still in tact. However, customers want to prevent EPS from operating when issues occur repeatedly across ignition cycles. Nexteer’s strategy is to provide NTCs for each issue to be tracked.
Diagnostic Overview:
Input signal IvtrIdptSig_Cnt_u08 represents the currently active number of Inverters. When the number of independent signals is equal to or less than a calibration in LoaMgr, the fault status is set instantly to Failed. LoaMgr can react instantly because the function providing the input signal is expected to debounce before dropping to a lower value.
Typical Fault Response: F3 Notification Only
The diagnostic is set to an F3. The fault is intended to produce not immediate change in system behavior. Its purpose is to allow disabling of EPS at the beginning of the Nth ignition cycle.
Probable Sources (Most to Least Probable):
•This fault should never get used in single-inverter EA3 programs because the IvtrIdptSig_Cnt_u08 input port of LoaMgr will remain disconnected. There is no upstream function to send this signal into LoaMgr.
•Fault may be active because the threshold calibration value is set too high. For a single-inverter design, threshold cal should be zero. For a dual-inverter design, threshold cal should be zero or one.
•Fault may be active because LoaMgr input port was not stubbed out with the correct Initial Value. Should be stubbed with a value of 2.
Initialization | |
Periodic | |
Event | X |
Date | Revision | Initials |
3/27/2015 | Initial Release | Kevin Derry |
Description of Unusual Event setting NTC | Root Cause / Explanation |
Date | FDD & Rev | Modifications to Diagnostic Function |
3/27/2015 | SF049A v1.0.0 | Initial Implementation |
Algorithm Changes / Lessons Learned / Revision Log
SF049A_LoaMgr_v1.0.0
•Data Dictionary report shows errors due to bug in VerifyDD tool. DataDict.Constants are named in ALL CAPS, so the tool thinks that units are spelled wrong (CNT instead of Cnt).
| Instructions for Functional Design Package Peer Review | ||
| PRE-MEETING | ||
| Function Owner | Confirm that requirements are reviewed and approved PRIOR to the FDP peer review | |
| Function Owner | Start with latest version of the template for any "first reviews" - Continue to use existing temmplate for re-reviews | |
| Function Owner | Provide the functional design package (changed documents) to the invited attendees 1-2 working days in advance of review | |
| Function Owner | Notify the assigned peer reviewer and make sure they are prepared to do their function in the meeting | |
| Function Owner | Identify necessary attendance and invite to meeting | |
| Function Owner | Complete the "Author" column information for sections 1 through 3 prior to the review | |
| Function Owner | Complete the attendance invitation list in section 5 | |
| Function Owner | For Re-reviews only: Complete the column "remarks by author" to identify actions taken to address items found in earlier reviews. | |
| DURING MEETING | ||
| Function Owner | Present document changes to the review team | |
| Peer Reviewer | Capture attendance of the review | |
| Peer Reviewer | Capture actions and issues in section 4. Identify issue summary, Document type, Reference (Requirement ID, section number, etc), Defect Type and indicate status as "OPEN" | |
| POST MEETING | ||
| Function Owner | Follow up on all "open" items. Update "Summary of Resolution" to indicate what was done or decided. | |
| Function Owner | Schedule follow up review OR review open items with peer reviewer and obtain agreement to close | |
| Peer Reviewer | Close change request in system and confirm all associated tasks are complete. Upload peer review checklist (this document) with any FDP updates |
| Rev | Change | Author |