justin
6eb449f354
Direct on-truck measurement with the verified 1446 ICP PID: peak cranking ICP 376 psi vs the ~500 psi firing threshold. FICM Main min 48.0 V (healthy), battery min 10.3 V (adequate). Diagnosis empirically confirmed: high-pressure oil bleeds off during cranking. 376 psi is "almost there" not zero, which fits a partial leak (IPR seat / oil rail O-rings / partial STC crack) rather than a fully blown STC fitting. - Capture the --crank output in crank-test-2026-06-30.txt - Add EMPIRICAL CONFIRMATION section to diagnostics README - Update handoff "resume at the truck" to lead with physical inspection (IPR -> STC -> oil rail O-rings), since the OBD-side diagnosis is done Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
ford-obd
Minimal ELM327 OBD-II code reader with a Ford 6.0L Power Stroke no-start triage, built for a cheap CH340 ELM327 USB adapter. Works on any OBD-II vehicle for generic codes/PIDs; the triage notes are 6.0-specific.
Created as a stopgap while forscan.org was offline — it covers reading/clearing codes and the basics, not Ford-enhanced diesel PIDs (see Scope below).
Features
- Read stored (mode 03), pending (mode 07), permanent (mode 0A) DTCs
- Decode P/C/B/U codes, with common 6.0 codes described and no-start suspects flagged
- Clear codes (mode 04) — guarded behind
--clear+ a typedCLEARconfirmation, then re-reads to show any code that returns immediately (active fault) - Key live values (coolant, IAT, MAP, module voltage, RPM, load, throttle) + battery voltage
- 6.0 Power Stroke no-start triage checklist (FICM, ICP, cam/crank, batteries, fuel)
Setup (Windows)
- Install the CH340 driver (WCH
CH341SER) so the adapter appears asUSB-SERIAL CH340 (COMx)in Device Manager → Ports. - Install Python from https://www.python.org/downloads/ — tick Add Python to PATH.
Usage
python obd_reader.py # auto-detect the COM port
python obd_reader.py COM5 # force a port
python obd_reader.py COM5 9600 # force port + baud (default 38400)
python obd_reader.py COM5 --clear # read, then optionally clear (asks to confirm)
python obd_reader.py COM5 -v # verbose: show raw ELM327 traffic
Crank monitor (dedicated no-start view) — --crank
The one to use for a crank-but-won't-start. Big ICP readout with a wide bar
(the | marks the 500-psi firing threshold), a rolling ASCII trace of the
ICP build-up, peak-hold, FICM/battery/RPM with sag tracking, and a pass/fail
verdict. Start it, then crank.
python obd_reader.py COM5 --crank # crank monitor
python obd_reader.py COM5 --crank --dash-log crank.csv # + record a CSV
ICP [#################################|##----] 539.8 psi
PEAK 540 psi FIRING PRESSURE REACHED
FICM Main 47.5V (min 47.5) [DOC] Batt 12.6V (min 10.7) RPM 200
ICP trace (psi vs time, last 16 samples)
600 |
500 |----------------------------------------------#### <- firing line
| ######
| ########
+--------------------------------------------------
Read it: ICP should climb past 500 psi within 1–2 s of cranking
(FIRING PRESSURE REACHED, green). If it stalls below 500 (red, trace flat
under the line), that's the high-pressure oil bleed-off — STC fitting / oil-rail
O-rings. On exit it prints the peak and a verdict. q quits, r resets.
Live dashboard (real-time gauges)
Updates in place as you crank or run the engine — color-coded, with live
min/max so a crank's peak ICP is captured. No extra dependencies (ANSI;
works on any Windows 10+ terminal). q quits, r resets min/max.
python obd_reader.py COM5 --dash # vitals preset (ICP, FICM, IPR, batt, RPM, temps)
python obd_reader.py COM5 --dash crank # cranking preset: ICP / FICM main / batt / RPM (fastest)
python obd_reader.py COM5 --dash full # every PID
python obd_reader.py COM5 --dash crank --dash-log crank.csv # + write a CSV while you watch
No-start use: run --dash crank, then crank. A healthy 6.0 builds
~500+ psi ICP within 1–2 s; if ICP stalls below 500 (red), that confirms
the high-pressure oil bleed-off. FICM Main should hold ~48V. The --dash-log
CSV is your streaming log — paste it back for analysis.
Note: the FICM PIDs (09xx) are [DOC] (not yet confirmed on this truck); if
they read --, they auto-drop after a few frames so the refresh rate stays up.
Or just double-click RUN_OBD.bat on Windows (auto-installs pyserial).
On the truck: plug into the OBD port under the dash, key to RUN (engine off is fine for codes), then run the tool.
Scope / honesty
A generic ELM327 reads standard OBD-II only: codes, generic PIDs, port voltage. It does not read Ford-enhanced diesel PIDs (ICP, FICM main/sync voltage, IPR%) — those need FORScan. For FICM/ICP numbers, measure at the FICM with a meter, or use FORScan when it's available. Default baud is 38400 (measured on the CH340 adapter); try 9600 if you get garbage.
Requirements
pyserial (pip install pyserial). Tested against a QinHeng CH340 ELM327 v1.5 clone.