CV1 Practice Vehicle — Service Reference v1.0

CV1 has one cylinder bank. Cylinder 1 is at the timing-chain end; cylinders run 1–2–3–4 along the block. One engine control module (ECM) controls injection, ignition, dual cam phasing, electronic throttle and emissions. Separate fuel-pump, transmission and body modules share the powertrain CAN bus.

Each cylinder has one solenoid GDI injector and one smart coil-on-plug unit. CV1 has no port injectors, distributor, waste-spark coil, idle-air bypass valve, variable valve lift, cylinder deactivation or secondary-air pump. A fixed-geometry turbo uses an electric wastegate and a separate compressor recirculation valve.

Fresh air passes through the filter and MAF sensor, compressor, charge-air cooler, charge-pressure sensor, throttle and manifold. MAP measures pressure after the throttle. The single exhaust path contains the turbo turbine, upstream wideband sensor, three-way catalyst, downstream switching oxygen sensor and gasoline particulate filter (GPF), in that order. The original overview figure shows flow relationships, not physical distances.

The prescribed reference fuel is fictional E10 gasoline with a training stoichiometric air/fuel mass ratio of 14.1:1. Lambda equals actual air/fuel ratio divided by 14.1. Closed-loop operation normally targets lambda 1.00; specified high-load operation targets 0.88. A model condition or test command stated in a question takes precedence over a normal-operation snapshot, but does not change this vehicle's hardware or calibration.

Use the compression limits only with ECT 80–100 °C, all plugs removed, injection and ignition inhibited by the CV1 service command, an open throttle service setting and cranking speed 220–260 rpm. A relative-current test locates a weak contribution; it does not by itself distinguish rings, valves, a cam event or starter commutation.

Leakage is tested at the suspect cylinder's compression TDC with both valves closed and a regulated 600 kPa gauge air supply. Escaping air at the intake, tailpipe or crankcase identifies the observed path; inspect the corresponding mechanical parts rather than treating a leakage percentage as a component identity.

All four cylinder displacements are equal. For calculations use 498.8 cm³ swept volume per cylinder and 52.5 cm³ clearance volume; these rounded values are consistent with the nominal bore, stroke and 10.5:1 ratio within rounding. A four-cylinder four-stroke engine has two firing events per crank revolution. Rotating crank orders and firing-event orders are distinct.

CV1 has a metered PCV path from its separator to the intake manifold and a check valve that closes that path under boost. A separate separator outlet admits vapor to the compressor inlet under boost. The mechanical pressure limits below require both paths to be unobstructed; an intake-only smoke check does not establish crankcase ventilation flow.

Connector references describe the harness cavity number as seen from the harness terminal face, never a mirrored wire-entry view. ECM X1 carries power and analog inputs, X2 output drivers, X3 synchronization/network/motor circuits, and X4 oxygen-sensor interfaces. Pins not listed are unused. Sensor returns must not be substituted for high-current chassis grounds.

F1 supplies ECM keep-alive power at X1-1. Main relay K1 supplies switched power at X1-2 and the separately fused coil, FPCM and actuator branches. K1 coil has fused battery positive; ECM X3-12 pulls its other end low. With a valid wake request the ECM holds K1 during RUN/START and for 20 seconds after key-off to save diagnostic state. No relay-control bypass is part of a CV1 test.

ECM power grounds X1-3 and X1-4 share engine ground G101. FPCM uses body ground G102. Sensor return A at X1-6 and return B at X1-8 join separate low-current internal ECM return nodes. Regulators A and B are electrically independent and each has a 100 mA current-limited output; one shorted branch can be isolated without assuming the other is healthy.

Measure a loaded drop across the identified path, not just its resistance while disconnected. The acceptance limit for each ECM B+ feed is 0.30 V from battery positive to its ECM pin during cranking, and for each ECM ground is 0.10 V from its ECM ground pin to battery negative during cranking. A feed must also remain at least 9.6 V. An ECM voltage below 9.0 V for more than 10 ms resets the controller.

CV1 powertrain communication uses one 500 kbit/s high-speed CAN backbone. ECM and BCM are the two physical ends, each with a 120 Ω termination across CAN-H and CAN-L. TCM and FPCM are non-terminated stubs. The diagnostic connector attaches to this backbone at the BCM junction; there is no independent diagnostic CAN termination.

For the resistance test, key off, wait two minutes, disconnect battery negative and confirm zero bus voltage. With both ends connected the harness measures 60 Ω nominal across DLC pins 6 and 14; disconnecting exactly one intact terminated end leaves 120 Ω. A stub disconnect alone leaves both terminations. An unpowered 60 Ω reading does not prove successful powered communication.

When powered and awake, CV1's recessive CAN-H and CAN-L are both about 2.5 V to ground. A dominant bit is about 3.5 V on H and 1.5 V on L. Capture both lines and their differential signal; a slow average voltage does not show bit timing or a short dropout. These are this training network's nominal waveform levels.

Messages contain a rolling counter and checksum. A newly received frame is not considered valid state if either fails. ECM accepts start only after a current authorization and Park/Neutral message. An old but otherwise well-formed message does not satisfy freshness. The status rules below describe fallback behavior, not instructions to bypass authorization.

All transfer functions here are CV1 calibrations, not generic sensor rules. V means signal voltage measured relative to its assigned sensor return. Ratiometric formulas assume a measured 5.00 V reference; if the measured reference is different, multiply the stated voltage by actual reference / 5.00 before comparing. MAF has a regulated output and is not ratiometric to either external 5 V branch.

MAP is after the throttle; CHARGE_P is before it. Both measure absolute pressure using the same pressure calibration. BARO has a separate absolute-pressure sensor. At KOEO with air pressures equalized, all three should agree within 3 kPa. During normal warm idle CHARGE_P remains close to BARO while MAP is much lower.

ECT and IAT are NTC thermistors, each to return A, with separate internal 2.49 kΩ pull-ups to the ECM's internal logic 5.00 V supply, not to external reference A or B. Their formula is V = 5R/(2490 + R). An open thermistor signal approaches 5 V and a signal shorted to its return approaches 0 V. The resistance values are reference points; do not invent a linear resistance-versus-temperature interpolation unless a question supplies it.

The ECM declares an analog circuit electrical fault below 0.15 V or above 4.85 V for 100 ms. A signal within those bounds may still be biased or implausible. The raw-voltage PID always reports the measured pin voltage. An invalid pressure signal's substituted engineering-value PID is explicitly marked substituted and is not evidence that its sensor is accurate.

The crank wheel has 60 equally spaced 6-degree positions with two adjacent teeth missing: 58 physical rising edges per revolution. The normal tooth interval spans 6 crank degrees; the interval across the missing pair spans 18 degrees. A crank reference is the first rising edge after the long interval. It is 60 degrees before cylinder 1 compression TDC on the cycle identified by the cam sensors; the next revolution's reference is not another cylinder 1 compression TDC.

With both phasers parked at zero, the unique intake-cam rising edge occurs 96 crank degrees after that cylinder-1-cycle CKP reference and the unique exhaust edge at 156 degrees. Each unique cam edge recurs every 720 crank degrees. All CV1 scan-tool cam angles are crank degrees. Positive intake advance moves its edge earlier; positive exhaust retard moves its edge later.

Start synchronization requires CKP speed at least 120 rpm, both valid cam patterns and authorized start. Losing one cam signal after synchronization permits fixed zero-target operation with a diagnostic fault. Losing CKP for 50 ms stops injector/coil commands; loss of a CMP does not grant permission to reinterpret an arbitrary CKP gap as cylinder 1.

Oil-control valves receive K1 power and ECM low-side PWM at 200 Hz. PWM duty is energized low-time, not the high-time of a voltage-to-ground capture. Oil pressure supplies phaser movement; a current-correct valve does not establish oil delivery or mechanical movement. Parked correlation checks use the CV1 zero-target service command and physically verified lock positions; unplugging a valve alone does not prove it has parked.

Each smart coil has terminal 1 K1/F3 battery supply, terminal 2 local cylinder-head power ground, terminal 3 its ECM X2 logic trigger, and terminal 4 a low-current diagnostic return to return A. Primary switching is inside the coil. The 5 V trigger is not a direct primary negative terminal and cannot be used as the 300 V primary waveform test point.

A logic-high trigger charges the coil; its falling edge requests firing. At the prescribed 14.0 V bench condition, a healthy coil reaches 7.0 A after 3.0 ms and requests spark within 80 µs of the trigger falling edge. At 10.0 V its commanded charge interval extends to 4.0 ms. The spark interval and charging interval are separate portions of the event.

CV1 uses individual COP circuits, not a companion-cylinder series-secondary path. Label traces from cylinder 1's independently verified trigger and the firing order, not a scope's default cylinder labels. With compression TDC 1 at 0°, the other compression TDCs are cylinder 3 at 180°, cylinder 4 at 360° and cylinder 2 at 540°.

Use the prescribed COP pickup for secondary comparisons and the approved isolated training-coil fixture for direct primary captures. Comparing voltage magnitudes requires the same probe, orientation, attenuation and pressure condition. A rising firing-voltage demand under boost can be normal; a new early extinction or missing energy must be evaluated with gap, coil current and cylinder condition.

The in-tank pump feeds a filter and low-pressure line to the mechanical HP pump inlet. There is no low-pressure fuel return line at the engine. A gauge tee immediately before the HP pump must agree with LOW_P at ECM X1-12 within 20 kPa. LOW_P is gauge pressure; rail pressure in the next section is absolute.

FPCM terminal 1 is K1/F4 power, terminal 2 G102 power ground, terminal 3 dedicated ECM command from X2-13, terminal 4 motor-duty feedback to X2-14, terminals 5/6 CAN-H/L, terminal 7 the LOW_P signal tee also feeding ECM X1-12, and terminal 8 a high-impedance analog-return sense connected to sensor return A. Its pressure loop reads terminal 7 differentially relative to terminal 8, not relative to its motor power ground. CAN status is not the pressure command path. The LOW_P transducer uses reference A and return A, not an independent FPCM supply/calibration.

ECM command is 2.00 kHz PWM, with duty defined as logic-high time. The discrete command codes below select a pressure target; they are not motor voltage duty. Feedback is 1.00 kHz logic PWM with high duty equal to the actual pump motor energized duty. Thus a 40% command and a 62% feedback can be a normal regulated state, not a 22-point command error.

KOEO authorization causes a 2.0-second prime. Without continued valid cranking or running the ECM then commands off. A failed CAN status does not by itself stop the dedicated PWM command. If the command wire is invalid for 100 ms while K1 remains on and the last accepted state was running, FPCM uses a fixed 70% motor duty for at most 5.0 seconds, reports fallback, then switches off. This fallback is not a regulated 70% pressure target.

The intake cam drives the HP pump through a three-lobe follower, giving three pump strokes per cam revolution, or 1.5 pump strokes per crank revolution. Its inlet spill valve is normally open. During a delivery stroke the energized valve closes the spill path; a longer correctly timed energized interval retains more stroke delivery. Electrical duty without phase and inlet-pressure evidence is insufficient to prove pumping.

RAIL_P measures absolute rail pressure. The rail-to-cylinder delivery pressure is rail absolute minus cylinder absolute at injection; do not subtract manifold vacuum as though this were port injection. The rail's pressure-relief valve opens at 19 MPa absolute and returns relieved fuel to the HP pump low-pressure inlet, not directly to the tank.

Each injector has a floating two-wire boosted driver, with a 65 V differential opening phase, 8.0 A peak and 2.0 A hold in the prescribed bench command. Either individual wire can change common-mode voltage while the differential pulse remains unchanged. Never treat either injector terminal as a permanent ground or connect a normal test lamp to these outputs.

All HP opening, collection and injector tests are described only as readings from an approved enclosed training fixture. Real GDI fuel can remain hazardous after key-off; the fiction does not authorize loosening a pressurized line. The CV1 pressure-release service routine is complete only when the independently verified rail pressure is below 0.20 MPa absolute and the fixture declares its isolation checks passed.

CV1 meters idle air with the main electronic throttle. Motor pins X2-23 and X2-24 are an H-bridge pair. Positive voltage from X2-23 to X2-24 opens the plate; reversed differential voltage closes it. Equal voltages produce zero applied motor voltage even if each pin reads battery voltage to ground.

Throttle travel is normalized 0–100% between the learned physical closed and fully open stops; it is not an angle in geometric degrees. The spring rests at 8% travel with the motor de-energized. APP is normalized pedal travel, not a request that the throttle must match numerically. The ECM considers load and torque requests when converting pedal into throttle demand.

At KOEO the permitted service sweep is 10–60% travel with the engine stopped and fingers/tools outside the plate. A valid tracking test needs both calibrated TP signals and independent physical plate movement. The motor-position agreement requirement is different from APP redundancy agreement.

A latched TP correlation or throttle motor fault disables motor drive, leaves the spring at 8% travel and limits engine speed by fuel/spark to 1800 rpm. One valid APP with the other invalid allows at most 25% requested torque after plausibility checks; two invalid APP channels produce idle-only demand. These fictional strategies apply to CV1, not to every electronic throttle.

CV1's wastegate bypasses exhaust around the turbine; 0% position is seated and 100% fully open. The electric actuator uses X3-3/4 differential drive and X1-18 calibrated position feedback. With drive absent its spring moves the gate to 100% open. Opening the gate reduces turbine drive under comparable conditions; it is not a fresh-air recirculation valve.

The separate compressor recirculation valve opens a passage from compressor outlet back to compressor inlet during a rapid throttle closure. It is commanded shut during steady boosted load. The MAF lies before the compressor and after the air filter; the recirculation return enters after the MAF so internal recirculated air does not pass through the MAF again.

CHARGE_P lies after the cooler and before the throttle. In the prescribed loaded test, the throttle is sufficiently open that CHARGE_P exceeds MAP by no more than 8 kPa. MAP gauge boost equals MAP absolute minus BARO absolute. A compressor pressure ratio instead uses its own outlet and inlet absolute pressures; it is not MAP divided by an unrelated gauge number.

Use the CV1 150 kPa gauge charge-path isolation test only in the approved stopped-engine fixture. The test isolates compressor outlet through cooler to throttle inlet, holds temperature constant and separately checks test-tool leakage. A passing pressure hold does not establish a correct wastegate position or adequate turbine energy under load.

CV1 has one bank and a wideband upstream sensor between turbine outlet and the TWC. A dedicated ECM pump-cell controller converts its current into measured lambda. The raw upstream interface is not a 0–1 V switching-oxygen signal. The downstream sensor after the TWC is a conventional switching sensor referenced to return B.

The cooled high-pressure EGR path takes exhaust upstream of the turbine, passes it through an EGR cooler and motor-operated valve, and introduces it after the throttle. EGR is shut at idle, during cold start and during the prescribed boosted-load snapshot. Normal EGR enable requires ECT 70–105 °C, 1500–3000 rpm and MAP 55–95 kPa absolute, with exhaust pressure greater than manifold pressure and no disabling fault.

The controlled EGR comparison holds speed and total cylinder air-plus-EGR mass constant using the approved fixture; valid MAF and independent EGR-flow measurements are available. In that specific comparison, increasing EGR replaces fresh air and reduces MAF. A matched EGR-position signal shows valve travel, not necessarily flow through its cooler/passages.

Positive STFT/LTFT adds fuel; negative values remove it. Corrections are multiplicative, not simply added. Corrected upstream lambda near 1.00 can coexist with a significant mixture fault because feedback is compensating. Exhaust air leaks before the upstream sensor can corrupt feedback even if fuel delivery hardware passes.

The CV1 catalyst monitor compares completed lean–rich–lean cycle counts, not voltage amplitude across unlike sensor types. An upstream cycle must cross lambda 1.05, then 0.95, then 1.05; a downstream cycle must cross 0.20 V, then 0.75 V, then 0.20 V. The controlled monitor window lasts 60 seconds and contains at least ten upstream cycles. Its downstream/upstream cycle-count ratio must be at most 0.20 after accounting for the same gas-parcel window.

The GPF traps solid particles downstream of the switching oxygen sensor. Its prescribed differential-pressure measurements are supplied by the service fixture, not by an additional ECM input. The CV1 regeneration comparison concerns oxidizable soot; retained noncombustible ash and physical substrate damage require separate checks. Passing HC/CO/NOx channels does not quantify solid particle number.

Fuel-tank vapor enters the carbon canister. The purge path connects the canister to the intake after the throttle; the vent path connects the canister through a filter to atmosphere. Purge is normally closed; energizing its low-side driver opens it. Vent is normally open; energizing its driver seals it. Commands describe energized duty/state, not a sensor that directly measures flow.

Tank pressure uses branch B and the sensor calibration in this book: zero gauge is 2.50 V and negative pressure gives lower voltage. When vent is open and pressure has equalized, the independent gauge and PID should both be near zero gauge. A offset signal can falsely appear to show vacuum even before any pump or purge action.

The running leak test closes vent, meters purge until tank vacuum is −0.80 kPa gauge, then closes purge and observes pressure recovery in an isolated vapor space. Conditions must remain stable; tank vapor generation, changing temperature and fuel slosh can invalidate the comparison. A closed-command indication does not prove either valve is sealed.

The prescribed external smoke comparison is at most +0.50 kPa gauge using the approved vapor-safe training fixture. First establish fixture tightness and confirm the vent's requested state. Do not use unrestricted shop air or infer a specific leak size from an uncalibrated pressure-decay result. The CV1 monitor limits are fictional, not an inspection-law threshold.

The labels CV1-SENSOR, CV1-MISFIRE, CV1-FUEL, CV1-CAT, CV1-EGR and CV1-EVAP are fictional case labels, not SAE DTC numbers. Use the actual observed subsystem, electrical checks and operating conditions; a label alone does not identify a failed component. Capture stored, pending and permanent status plus the freeze frame before any permitted clear operation.

For CV1, a diagnostic trip is a RUN cycle in which the particular monitor's enable conditions are met and the monitor reaches a pass or fail decision. Starting and stopping the engine without that decision is not a completed trip for that monitor. A completed failed test can set readiness complete; ready does not mean fault-free.

The first completed failing trip for ordinary CV1 fuel/catalyst/EGR/EVAP faults records pending status and a freeze frame. A second consecutive completed failing trip confirms the fault and requests the MIL. A completed passing trip between failures breaks consecutiveness. Catalyst-damaging misfire instead requests an immediate flashing MIL and the affected cylinder's injector cut.

A permitted diagnostic clear removes ordinary stored/pending codes, the retained freeze frame and accumulated noncontinuous readiness. It does not repair a circuit, clear a permanent code, erase this book's calibrations or establish monitor passes. A separate explicit adaptation-reset command resets learned fuel trims; ordinary code clear does not. Battery removal also does not clear CV1 permanent codes.

A CV1 permanent fault is removed by the ECM after the responsible monitor completes and passes on three subsequent qualifying trips with no recurrence, never by the tester's ordinary clear request. These invented retention rules teach state interpretation and are not a claim about any jurisdiction's legal inspection requirements.

These are stabilized healthy reference snapshots at BARO 100 kPa, battery 13.8–14.4 V and E10 reference fuel, unless stated otherwise. Do not transplant an idle number into a load, warm-up or actuator service test. Each snapshot includes operating conditions; target and actual are separate PIDs.

All pressure PIDs include an absolute/gauge unit label. RAW_VOLTAGE is a measured input, VALUE is its calibrated engineering value, VALID identifies whether that value is sensor-derived, and SOURCE distinguishes measured from substituted. A matching target and substituted actual number is not a passing physical measurement.

The fixture's boost-load snapshot uses 3000 rpm, MAP 180 kPa, EGR and purge closed, lambda target 0.88 and rail target 14.0 MPa. Load and fuel state affect scan ranges. The 2500 rpm no-load snapshot is in Park, EGR/purge closed and lambda target 1.00; it is not the separate loaded EGR comparison.

The fictional dry gas analyzer's validated warm-idle reference uses its calibration-checked channels, no dilution/exhaust leak, matched parcel arrival and gas-basis settings. Those bands support CV1 diagnostic comparisons only. They do not claim a regulatory emissions pass for any real vehicle.

Treat this reference as a set of explicit case assumptions. Every fictional service limit is attached to its measurement location, operating condition and units. Compare the observed value to the applicable condition before deciding it fails. All limits are inclusive unless a question explicitly supplies a different decision rule.

Use independent mechanical measurements to validate a sensor, differential voltage to validate a floating motor/injector drive, actual motion/flow to validate actuator output, and matched captures to validate event timing. Electrical continuity or an accepted command alone does not establish loaded delivery or physical movement.

The book does not supply hands-on instructions for disabling protection, opening hazardous fuel circuits or bypassing authorization. Questions may describe safely isolated training fixtures. Use rated probes, isolated fixtures and validated measurement setups stated in each question; never infer approval for a real vehicle from CV1 values.

For a controlled comparison, hold all conditions named as matched constant. If a needed condition is missing, identify the missing evidence rather than inventing it. State changes such as a clear, learning reset, substituted PID, gas-parcel delay or enabled service override can change the meaning of a reading without repairing the underlying hardware.