Engine Controls - Diagnostic Methods - (Hybrid): Other Ford Escape I facelift

Vehicle Check/Preparation

Before using the diagnostic tool to carry out any test, refer to the Important Safety Notice located in the INTRODUCTION- HYBRID article and the necessary visual checks listed below.

Visual Checks

1. Inspect the air cleaner and inlet duct.
2. Check all engine vacuum hoses for damage, leaks, cracks, kinks and proper routing.
3. Check the powertrain control module (PCM) or transaxle control module (TCM) wiring harness for proper connections, bent or broken pins, corrosion, loose wires and proper routing.
4. Examine all high voltage cables and connectors for secure connection, damaged, burned or overheated insulation and loose or broken condition.
5. Verify the traction battery high voltage service plug is properly connected.
6. Verify the front and rear inertia fuel shutoff (IFS) switches are not tripped.
7. Check the powertrain control module (PCM), sensors, and actuators for physical damage.
8. Check the engine coolant for proper level and mixture.
9. Check the motor electronics coolant for proper level and mixture.
10. Check the transaxle fluid level and quality. Refer to the «AUTOMATIC TRANSAXLE/TRANSMISSION - ELECTRONICALLY CONTROLLED CONTINUOUSLY VARIABLE TRANSMISSION (eCVT) - HYBRID ESCAPE»(ref-232216) .
11. Make all necessary repairs before continuing with the quick test.

Vehicle Preparation

1. Carry out all safety steps required to start and run vehicle tests. Apply the parking brake, place the gear selector firmly into the PARK position and block the drive wheels.
2. Verify the high voltage traction battery state of charge (SOC) is equal to or greater than 45% by monitoring the traction battery control module (TBCM) SOC PID. If the monitored PID displays the SOC below 45%, start and idle the engine with full A/C ON.
3. Turn the A/C on and verify it functions correctly.
4. Turn off all electrical loads, such as radios, lamps, A/C, blower, and fans.
5. Start the engine and bring it up to the normal operating temperature before running the quick test.

Generic OBD PID List

An X in the Freeze Frame column denotes both a mode 1 and mode 2 PID (real time and freeze frame).

GENERIC OBD PID LIST

CL = Closed loop using HO2S(s) as feedback for fuel control.

OL DRIVE = Open loop due to driving conditions (heavy acceleration).

OL FAULT = Open loop due to fault with all upstream HO2S sensors.

CL FAULT = Closed loop fuel control, but fault with 1 upstream HO2S sensor.

Ford PCM PID List

FORD PCM PID LIST

Ford TCM PID List

FORD TCM PID LIST

FREEZE FRAME DATA TABLE

FREEZE FRAME DATA TABLE

Some unique parameters (PIDs) are stored in the keep alive memory (KAM) of the powertrain control module (PCM) to help in diagnosing the root cause of misfires. These PIDs are collectively called misfire freeze frame (MFF) data. These parameters are separate from the generic freeze-frame data that is stored for every malfunction indicator lamp (MIL) code. They are used for misfire diagnosis only. The MFF data is more useful for misfire diagnosis than the normal diagnosis only. It is captured at the time of the highest misfire rate and not when the DTC is stored at the end of a 1,000 or 200 revolution block. (Generic freeze-frame data for misfire can be stored minutes after the misfire actually occurred.)

Note. MFF PIDs are supported on all vehicles but may not be available on all diagnostic tools because enhanced PID access may vary by diagnostic tool manufacturer.

MISFIRE FREEZE FRAME PIDs

MISFIRE FREEZE FRAME PIDs

Non-Emission Related Freeze Frame Data

Freeze frame data allows access to non-emission related values from specific manufacturers PIDs. These values are stored when a non-emission related DTC is stored in continuous memory. This provides a snapshot of the conditions that were present when the DTC was stored. Once 1 set of freeze frame data is stored, this data remains in memory even if another DTC is stored. When a DTC associated with the freeze frame data is cleared or a KAM reset is carried out, new freeze frame data will be stored again.

NON-EMISSION FREEZE FRAME DATA TABLE

NON-EMISSION FREEZE FRAME DATA TABLE

Flash Electrically Erasable Programmable Read Only Memory (EEPROM)

Making Changes to the VID Block

A PCM which is programmed may require changes to be made to certain VID information to accommodate vehicle hardware. Refer to PCM/Module Reprogramming on the diagnostic tool.

PCM Reprogramming

At certain times, the entire EEPROM needs to be completely reprogrammed. This is due to changes made to the strategy or calibration after production or the need to reset the VID block because it has reached its limit. Refer to PCM/Module Reprogramming on the diagnostic tool.

Note. After the PCM is successfully reprogrammed, clear any TCM DTCs that may have been stored during reprogramming.

Transaxle Control Module (TCM) Reprogramming

Drive Cycle Recommendations

1. Most OBD monitors complete more readily using a steady foot driving style during cruise or acceleration modes. Operating the throttle in a smooth fashion minimizes the time required for monitor completion.
2. Fuel tank level should be between 1/2 and 3/4 fill with 3/4 fill being the most desirable.
3. The evaporative monitor can only operate during the first 30 minutes of engine operation. When executing the procedure for this monitor, stay in part throttle mode and drive in a smooth fashion to minimize fuel slosh.
4. When bypassing the EVAP engine soak timer, the PCM must remain powered (key in ON position) after the clearing the continuous DTCs and relearning emission diagnostic information.

For best result, follow each of the following steps as accurately as possible

ON BOARD DIAGNOSTIC (OBD) DRIVE CYCLE TABLE

Recreating the Fault

Recreating the fault is the first step in isolating the cause of the intermittent symptom. A thorough investigation should start with the customer information worksheet located in the back of the book. If freeze frame data is available, it may help in recreating the conditions at the time of a malfunction indicator lamp diagnostic trouble code (MIL DTC). Listed below are some of the conditions for recreating the fault

CONDITIONS TO RECREATE FAULT CHART

Accumulating PCM Data

PCM data can be accumulated in a number of ways. This includes circuit measurements with a digital multimeter (DMM) or diagnostic tool PID data. Acquisition of PCM PID data using a diagnostic tool is one of the easiest ways to gather information. Gather as much data as possible when the fault is occurring to prevent improper diagnosis. Data should be accumulated during different operating conditions and based on the customer description of the intermittent fault. Compare this data with the known good data values located in TYPICAL DIAGNOSTIC REFERENCE VALUES . This requires recording data in 4 conditions for comparison: 1) KOEO, 2) HOT IDLE, 3) 48 km/h (30 mph), and 4) 89 km/h (55 mph).

Analyzing Data From Playback of Stored PIDs

Look for abnormal events or values that are clearly incorrect. Inspect the signals for abrupt or unexpected changes. For example, during a steady cruise most of the sensor values should be relatively stable. Sensors such as the TP, MAF and RPM that change abruptly when the vehicle is traveling at a constant speed are clues to a possible fault area.

Look for agreement in related signals. For example, if the APP1, APP2 and APP3 are changed during acceleration, a corresponding change should occur in TP1, TP2, LOAD, RPM and MAF V PIDs.

Make sure the signals act in proper sequence. An increase in RPM after the TP1 and TP2 are increased is expected. However, if RPM increases without a TP1 and TP2 change, then a fault may exist.

Table Format (Scheme 192): Scroll through the PID data while analyzing the information. Look for sudden drops or spikes in the values. (Refer to the following TP example in (Scheme 192) ). Notice the major jump in the TP voltage while scrolling through the information. This example would require a smooth and progressive accelerator pedal travel during a key ON and engine OFF mode.

Graph Format (Scheme 193): Scroll through the PID data while analyzing the information. Look for sudden drops or spikes in the linear lines showing the transformation of values to the line graph. This example requires smooth progressive accelerator pedal pressure with the key ON and the engine OFF.

Scheme 192

Scheme 193

Peripheral Inputs

Some signals may require certain peripherals or auxiliary tools for diagnosis. In some cases, these devices can be inserted into the measurement jacks of the diagnostic tool or DMM. For example, connecting an electronic fuel pressure gauge to monitor and record the fuel pressure voltage reading and capturing the data would help find the fault.

Comparing PCM Data

After the PCM values are acquired, it is necessary to determine the fault area. Typically, it requires the comparison of the actual values from the vehicle to the typical values from the TYPICAL DIAGNOSTIC REFERENCE VALUES .

Obtain Freeze Frame Data

Freeze frame data can be helpful in duplicating and diagnosing adaptive fuel concerns. This data (a snapshot of certain PID values, recorded at the time the DTC was stored in continuous memory) is helpful to determine how the vehicle was being driven when the fault occurred, and can be especially useful on intermittent concerns. Freeze frame data, in many cases, can help to isolate possible areas of concern as well as rule out others. Refer to FREEZE FRAME DATA for a more detailed description of this data.

Using the LONGFT1 PID

The LONGFT1 PID can be useful for diagnosing fuel trim concerns. A negative PID value indicates the fuel is being reduced to compensate for a rich condition, while a positive PID value indicates the fuel is being increased to compensate for a lean condition. It is important to know that there is a separate LONGFT value that is used for each RPM/load point of engine operation. When viewing the LONGFT1 PID, the value may change a great deal as the engine is operated at different RPM and load points. This is because the fuel system may have learned corrections for fuel delivery concerns that can change as a function of engine RPM and load. The LONGFT1 PID displays the fuel trim currently being used at that RPM and load point. Observing these changes in LONGFT1 can help when diagnosing fuel system concerns. For example

1. A contaminated MAF sensor results in a LONGFT1 correction value that is negative at idle (reducing fuel), but positive (adding fuel) at higher RPM and loads.
2. Vacuum leaks result in large, rich corrections (positive LONGFT1 value) at idle, but little or no correction at higher RPM and loads.
3. A plugged fuel filter results in no correction at idle, but large rich corrections (positive LONGFT1 value) at high RPM and load.

Air Measurement System

With this condition, the engine may actually run rich or lean of stoichiometry (14.7:1 air/fuel ratio) if the powertrain control module (PCM) is not able to compensate enough to correct for the condition. One possibility is that the mass of air entering the engine is actually greater than what the mass air flow (MAF) sensor is indicating to the PCM. For example, with a contaminated MAF sensor, the engine runs lean at higher RPM because the PCM delivers fuel for less air than is actually entering the engine.

Examples: MAF sensor measurement is inaccurate due to a corroded connector, contamination or dirty connector. A contaminated MAF sensor typically results in a rich system at low airflows (PCM reduces fuel) and a lean system at high airflows (PCM increases fuel).

Vacuum Leaks/Unmetered Air

With this condition, the engine may actually run lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition. This condition can be caused by unmetered air entering the engine, or due to a MAF malfunction. In this situation, the volume of air entering the engine is actually greater than what the MAF sensor is indicating to the PCM. Vacuum leaks normally are most apparent when high manifold vacuum is present (for example, during idle or light throttle). If freeze frame data indicates the fault occurred at idle, a check for vacuum leaks/unmetered air might be the best starting point.

Examples: Loose, leaking or disconnected vacuum lines, intake manifold gaskets or O-rings, throttle body gaskets, brake booster, air inlet tube, stuck/frozen/aftermarket PCV valve, and unseated engine oil dipstick.

Insufficient Fueling

With this condition, the engine may actually run lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition. This condition can be caused by a fuel delivery system concern that restricts or limits the amount of fuel being delivered to the engine. This condition normally is most apparent when the engine is under a heavy load and at high RPM, when a higher volume of fuel is required. If the freeze frame data indicates that the fault occurred under a heavy load and at higher RPM, a check of the fuel delivery system (checking fuel pressure with engine under a load) might be the best starting point.

Examples: Low fuel pressure, fuel pump, fuel filter, fuel leaks, restricted fuel supply lines, and fuel injector concerns.

Exhaust System Leaks

In this type of condition, the engine may actually be running rich of stoichiometry (14.7:1 air/fuel ratio) because the fuel control system is adding fuel to compensate for a perceived (not actual) lean condition. This condition is caused by oxygen (air) entering the exhaust system from an external source. The HO2S reacts to this exhaust leak by increasing fuel delivery. This condition causes the exhaust gas mixture from the cylinder to be rich.

Examples: Exhaust system leaks upstream or near the HO2S, and poorly welded/leaking HO2S boss.

With this condition, the engine may actually run rich or lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition. One possibility is that the mass of air entering the engine is actually less than what the MAF sensor is indicating to the PCM. For example, with a contaminated MAF sensor, the engine runs rich at idle because the PCM delivers fuel for more air than is actually entering the engine.

Examples: MAF sensor measurement is inaccurate due to a corroded connector, contamination/dirt. A contaminated MAF sensor typically results in a rich system at low airflows (PCM reduces fuel) and a lean system at high airflows (PCM increases fuel).

Fuel System

With this condition, the engine may actually run rich of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition. This situation can be caused by a fuel delivery system that is delivering excessive fuel to the engine.

Examples

1. Fuel injector leaks (injector delivers extra fuel).
2. EVAP canister purge valve leak (if canister is full of vapors, introduces extra fuel).
3. Fuel rail pressure sensor (electronic returnless fuel systems) concern causes sensor to indicate lower pressure than actual. PCM commands higher pressure to the fuel pump driver module (FPDM), causing high fuel pressure (system rich at all airflows).

Base Engine

Engine oil contaminated with fuel can contribute to a rich running engine.

Open Circuit (Continuity)

Disconnect the PCM. Measure the harness resistance between the suspect circuit at the harness connector and the appropriate PCM harness connector pin or PCM breakout box (if available). The resistance must be less than 5 ohms.

Shorts to Ground

Measure the harness resistance between the suspect circuit at the harness connector and a reliable ground (B-, chassis gnd or PWR GND at the PCM breakout box, if available). The resistance must be greater than 10,000 ohms.

Shorts to Power

Key ON to power up the power circuits. Measure the voltage between the suspect circuit at the harness connector and a reliable ground. The voltage must be less than 1 volt.