DESCRIPTION & OPERATION
The electric cooling fan system may consists of a single speed or 2-speed cooling fan or fans controlled by Powertrain Control Module (PCM), on all models, and through the Constant Control Relay Module (CCRM) on Escort and Mustang. On all models, a low speed fan control relay and/or a high speed fan control relay. The electric cooling fan or fans are activated when ignition switch is in ON position and engine coolant exceeds a specified temperature. On vehicles equipped with A/C, cooling fan is also active when A/C is on.
Note. Unless specified otherwise, references to Escort include Escort Coupe (ZX2). Villager is not covered in this article. See ELECTRIC COOLING FANS - EEC - VILLAGER article.
Note. This article only tests the Fan Control (FC) relay and Constant Relay Control Module (CCRM) circuits. Other test may be referenced while performing electric cooling fan diagnosis. For complete Ford EEC-V system diagnosis, see SELF-DIAGNOSTICS - EEC-V - GASOLINE article in ENGINE PERFORMANCE.
Description
KOEO on-demand self-test is a functional test of PCM performed with ignition key on, engine off. This test checks if PCM inputs and outputs are functioning electronically without any faults. A fault must be present at time of testing for KOEO on-demand self-test to detect a fault.
KOER on-demand self-test is a functional test of PCM performed with ignition key on, engine running. A check of certain inputs and outputs is made during operating conditions and normal operating temperature. The Brake Pedal Position (BPP) switch, Transmission Control Switch (TCS) and Power Steering Pressure (PSP) switch tests are part of KOER on-demand self-test and must be performed during this operation (if applicable). See BPP, PSP & TCS TEST PROCEDURES . A fault must be present at time of testing for KOER on-demand self-test to detect a fault.
Continuous memory self-test is a functional test of PCM performed under any condition (engine running or engine off) with ignition switch turned to ON position. Unlike KOEO and KOER self-tests which can only be activated on demand, continuous MONITOR & RECORD is always active in monitoring the system. When a fault is detected, DTC will be stored in memory. This makes it possible to diagnose intermittent faults.
There are 2 types of Continuous Memory DTCs. Emission related DTCs will illuminate the Malfunction Indicator Light (MIL) on instrument cluster. Non-emission DTCs will never illuminate MIL. On emission-related MIL codes, PCM will store DTC in continuous memory at first detection of problem. The MIL will not be illuminated, but DTC is considered by PCM to be a pending DTC. If same problem is detected in next drive cycle, MIL will illuminate. MIL will go out if fault is not present after 3 consecutive drive cycles, or PCM has been reset. An emission-related pending DTC or non-emission DTC will be erased after 40-80 warm-up cycles or PCM reset.
PARAMETER IDENTIFICATION MODE
Note. For complete listing of generic and Ford specific PIDs, see PIN VOLTAGE/PID VALUE CHARTS - CARS article or PIN VOLTAGE/PID VALUE CHARTS - TRUCKS article.
PID mode allows access to certain data values, analog and digital inputs and outputs, calculated values, and system status information. There are 2 types of PID lists available. The first is a Generic OBD-II PID list. This is a standard set of PIDs that all scan tools can access. The second is a Ford specific PID list that can be accessed by using New Generation Star (NGS) scan tool or Worldwide Diagnostic System (WDS). PID values are continuously updated when accessing PIDs from a specific PID list.
All OBD-II scan tools should be able to display OSR test. The OSR will display monitors on the vehicle and status of all monitors; complete or not complete. If not complete, the scan tool will display which MONITOR & RECORD has not completed. Comprehensive component, fuel and misfire monitors run continuously and will always display YES. Only a PCM reset, or keep alive RAM reset will cause non-continuous monitors to reinitialize to display NO.
FREEZE FRAME DATA MODE allows access to emission-related values from specific generic Parameter Identifications (PIDs). These PID values are stored when an emission-related DTC is stored in continuous memory and provide a snapshot of the conditions that were present when DTC was stored. See FREEZE FRAME DATA table.
| Acronym | Description | Measurement Units |
|---|---|---|
| ECT | Engine Coolant | Degrees |
| FUELSYS1 | Open/Closed Loop1 | OL/CL/OL, Drive/OL, Fault CL, Fault |
| FUELSYS2 | Open/Closed Loop2 | OL/CL/OL, Drive/OL, Fault CL, Fault |
| LONGFT1 | Long Term Fuel Bank1 | Percent |
| LONGFT2 | Long Term Fuel Bank2 | Percent |
| LOAD | Calculated Load Value | Percent |
| RPM | Engine RPM | Rev/Min |
| SHRTFT1 | Short Term Fuel Bank1 | Percent |
| SHRTFT2 | Short Term Fuel Bank2 | Percent |
| VSS | Vehicle Speed | MPH/KMH |
FREEZE FRAME DATA
Freeze frame data will remain in memory even if another emission-related DTC is stored, with exception to misfire or fuel system DTCs. When freeze frame data for a misfire or fuel system DTC is stored, it will overwrite any previous data and freeze frame data will not be overwritten. When freeze frame DTCs are erased or a PCM memory reset is performed, new freeze frame data will be stored. If multiple emission-related DTCs are stored in memory, always note freeze frame data DTC. Some unique PIDs are stored in PCM keep alive RAM to help in diagnosing root causes to misfires. See MISFIRE FREEZE-FRAME PIDS table.
Note. MFF PIDs are supported on all vehicles, but may not be available on all scan tools. Enhanced PID access may vary by scan tool manufacturer.
These unique PIDs are collectively called Misfire Freeze Frame (MFF) data. These PIDs are separate from generic freeze frame data that is stored for MIL codes and are used for misfire diagnosis only. MFF data is more useful for misfire diagnosis than normal diagnosis alone. MFF is captured at time of highest misfire rate, not when DTCs are normally stored at the end of a 1000 or 200 revolution block. Generic freeze frame data for a misfire can be stored minutes after a misfire actually occurs.
| PID | Description | PID No. | Units |
|---|---|---|---|
| MFF RPM | Engine RPM At Time Of Misfire | 16D3 | RPM |
| MFF LOAD | Engine Load At Time Of Misfire | 16D4 | PERCENT |
| MFF VS | Vehicle Speed At Time Of Misfire | 16D5 | MPH/KPH |
| MFF IAT | Intake Air Temperature At Time Of Misfire | 16D6 | DEGREES |
| MFF SOAK | Engine-Off Soak Time At Time Of Misfire | 16D7 | MINUTES |
| MFF RNTM | Engine Running Time At Time Of Misfire | 16D8 | SECONDS |
| MFF EGR | EGR DPFE Sensor At Time Of Misfire | 16D9 | VOLTAGE |
| MFF TP | Throttle Position At Time Of Misfire | 16DA | VOLTAGE |
| MFF T CNT | No. Of Driving Cycles At Time Of Misfire (At Least One 1,000 Rev Block) | 16DC | TRIPS |
| MFF PNP | 1= In Drive During Time Of Misfire | 16DD b1 | MODE |
| MP LRN | 1= Misfire Wheel Profile Learned In Keep Alive RAM | 16DD b0 | NONE |
MISFIRE FREEZE-FRAME PIDS
This mode allows a technician to energize and de-energize most of the system output actuators on command. After accessing OUTPUT TEST MODE, outputs and cooling fans can be turned on and off separately. OTM will turn off after vehicle is started or after cycling ignition switch off then on.
HARDWARE LIMITED OPERATIONAL STRATEGY (HLOS)
If a number of system or sensor failures are present and PCM is not receiving enough information to operate, PCM will switch to HLOS mode. PCM will output fixed values to allow operation of vehicle. Driveability concerns will be present. PCM will not output diagnostic trouble codes in this mode.
OBD-II Drive Cycle Description
EVAP MONITOR & RECORD will not activate if ambient air temperature outside is 40-100°F (4-38°C), or vehicle is in altitude above 8000 feet. If DTC P1000 has to be cleared when ambient air temperature outside is 40-100°F (4-38°C), or vehicle is above 8000 feet, PCM must detect these conditions once (twice on some models) before EVAP MONITOR & RECORD can be "bypassed" and DTC P1000 will clear. Perform EVAP MONITOR "BYPASS" PROCEDURE .
All OBD-II drive cycles must be performed using scan tool. Consult scan tool manufacturers instruction manual for drive cycle procedure. Vehicle should be driven at steady speeds during cruise or acceleration to help complete OBD-II monitors. Operate engine throttle in a steady fashion to minimize time required for MONITOR & RECORD completion. EVAP MONITOR & RECORD only operates during first 30 minutes of engine run time. If performing EVAP MONITOR & RECORD procedure, drive vehicle at a steady rate and at part throttle to minimize possible "fuel slosh".
Flash Electronically Erasable Programmable Read Only Memory (EEPROM) is contained in an Integrated Circuit (IC) inside of Powertrain Control Module (PCM). The EEPROM contains the vehicle strategy and any calibration information specific to vehicle. The IC is reprogrammable and at times it may become necessary to reprogram or reflash the entire contents. This is usually due to an after production strategy change or the Vehicle Identification (VID) area has been previously reprogrammed and has reached its limit. The VID block can be tailored to accommodate various hardware changes made since vehicle production. This procedure can only be performed using Ford's Service Bay Technical System (SBTS) or equivalent.
A replacement PCM will have a label stating PROGRAMMING REQUIRED. This indicates that it is necessary to retrieve VID data from the original PCM before removing PCM from vehicle. This procedure can be performed using New Generation Star (007-00500) scan tool or equivalent. See FLASH VEHICLE IDENTIFICATION (VID) BLOCK PROCEDURE . If original PCM is nonfunctional, it will be necessary to manually reprogram VID block. This procedure can only be performed using Ford's Service Bay Technical System (SBTS) or equivalent.
FLASH VEHICLE IDENTIFICATION (VID) BLOCK PROCEDURE
Note. If using a generic scan tool, follow scan tool manufacturer's instructions to perform FLASH VEHICLE IDENTIFICATION (VID) BLOCK PROCEDURE.
- To perform this procedure NGS scan tool, Ford Service Function (FSF) card and NGS Flash Cable (007-00531) must be used. Plug flash cable into scan tool. Plug other end of flash cable into Data Link Connector (DLC). From the scan tool main menu, select SERVICE BAY FUNCTIONS, POWERTRAIN CONTROL MODULE and then PROGRAMMABLE MODULE INSTALLATION.
- Scan tool display should show 2 selections. The first is selection is for old PCM information to be retrieved and stored. The second selection is for restoring new PCM with information that has been retrieved from the old PCM. Follow scan tool display instructions or refer to instruction sheet included with FSF card. If Vehicle Identification (VID) block has been reprogrammed previously, scan tool will display a message indicating the need to reflash entire Integrated Circuit (IC). This procedure can only be performed using Ford's Worldwide Diagnostic System (WDS).