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Engine Controls - Tests W/codes: Other Volvo V70 I

Testing & Diagnostics 5 illustrations ~7513 words

RETRIEVING & ERASING DTCs

CAUTIONNever disconnect or connect ECM connector with ignition switch in ON position.

Follow tool manufacturer's instructions if retrieving or erasing codes with Volvo Scan Tool (998-8686) or generic scan tool. See DIAGNOSTIC TROUBLE CODE IDENTIFICATION. Either scan tool must be connected to DLC located in console either on center console or underneath driver's side dashboard. (Scheme 32)

Scheme 32

Scheme 32
Scheme 32

Activating Components & Functions

Note. Components and functions can be activated individually with this function. Engine must not be running when activating components and functions.

Using scan tool in DIAGNOSTIC MODE, the following components can be activated

  1. PAIR Injection System Pump
  2. PAIR Injection System Solenoid
  3. Fuel Pump
  4. EVAP Valve
  5. EVAP Canister Shut-Off Valve
  6. Heated Oxygen Sensor (Front Or Rear)
  7. Engine Cooling Fan (Low Speed Or High Speed)
  8. Injector (No. 1, 2, 3, 4 Or 5)
  9. Idle Air Control Valve
  10. A/C Relay
  11. Engine Speed Signal To Combined Instrument Panel
  12. Engine Temperature Signal To The Combined Instrument Panel
  13. Malfunction Indicator Lamp
  14. Load Signal To Transmission Control Module

Reading Input & Output Signals

Note. Values and status of ECM input and output signals can be read with this function.

Using scan tool, the following parameters can be read

  1. Engine Speed
  2. Engine Temperature
  3. Engine Coolant Temperature Sensor Voltage
  4. Front Heated Oxygen Sensor Voltage
  5. Front Heated Oxygen Sensor Heating
  6. Rear Heated Oxygen Sensor Voltage
  7. Rear Heated Oxygen Sensor Heating
  8. Rear Heated Oxygen Sensor Compensation
  9. Fuel Trim Status
  10. Short-Term Fuel Trim
  11. Fuel Trim, Part Load
  12. Fuel Trim, Idling
  13. Fuel Trim, Status
  14. Injection Period
  15. Mass Air Flow Sensor, Voltage
  16. Load Tl
  17. MAF Sensor, Air Flow
  18. Throttle Angle
  19. Throttle Position Sensor, Voltage
  20. Throttle, Status
  21. Idle Air Control Valve, Air Flow
  22. Idle Air Trim
  23. Ignition Timing
  24. Status Ignition Timing Retardation Requested By TCM
  25. Knock Sensor No. 1 Status
  26. Knock Sensor No. 2 Status
  27. Fuel Enrichment Status
  28. Battery Voltage
  29. Vehicle Speed
  30. A/C Approved, Status
  31. A/C Relay, Status
  32. A/C Compressor, Status
  33. A/C Pressure
  34. A/C Pressure Sensor, Voltage
  35. Engine Cooling Fan, Status
  36. Operating Cycle, Status
  37. Trip, Status
  38. Warm-Up Cycle, Status
  39. Fault Active, Status
  40. Malfunction Indicator Lamp Lit, Status
  41. Lighting Of MIL Requested By TCM, Status
  42. Gear Selector Position, Status
  43. Canister Purge Valve
  44. Fuel Pump Relay, Status
  45. Fuel Shut-Off System, Status
  46. Acclerometer
  47. PAIR Injection System Pump, Status
  48. Flywheel Adaption, Status
  49. Flywheel Adaption B
  50. Flywheel Adaption C
  51. Flywheel Adaption D
  52. Flywheel Adaption E
  53. Temperature, Control Module
  54. EVAP Canister Shut-Off Valve, Status
  55. Fuel Tank Pressure
  56. Fuel Tank Pressure Sensor, Voltage

SYSTEM READINESS CODES

Note. Readiness codes will display READINESS=YES or NO after 2 TRIP cycles have been completed. Readiness codes may display INCOMPLETE at end of testing. This will not affect ODB-II function and can be disregarded.

Note. The following information is from Volvo technical service bulletin No. 0059, Section 2, Group 23, dated July, 2002.

Setting Instructions Using Volvo System Tester (VST)

For an example of screen display during testing (Scheme 33)

  1. Connect Volvo System Tester (VST) and read out fault memory. See «RETRIEVING & ERASING DTCs»(ref-15336-S41120021042000122900000) . Diagnose all DTCs before proceeding with system readiness check.
  2. Enter DIAGNOSTIC CHECK menu to verify that a TRIP cycle has been completed. If TRIP cycle has not been completed, see «TRIP DRIVING CYCLE USING VOLVO SYSTEM TESTER (VST)»(ref-15336-S15753875702004012900000) under DRIVE CYCLES. If TRIP cycle is complete, go to next step.
  3. Check flywheel adaptation status. If status is NOT READY, see «SETTING FLYWHEEL ADAPTATION USING VOLVO SYSTEM TESTER»(ref-15336-S18569199412004012900000) under PROGRAMMING. If status is READY, go to next step. NOTE: Ensure A/C is off during engine idling while testing. Compressor engagement will interrupt EVAP test.
  4. Check vehicle fuel level. Tank should be 1/4 to 3/4 full for accurate EVAP leakage detection completion. Adjust fuel level as necessary.
  5. Engine temperature must be between 84-122°F (29-49°C). If engine is above 122°F, shut engine off and allow it to cool down to within range.
  6. Move ignition key to position 2. Engine off. Access diagnostic check menu on scan tool and go to DTC 112. Start engine. Status of DTC 112 should change from NOT TESTED to TESTED. If status change happens, system readiness check is complete.

Scheme 33

Scheme 33
Scheme 33

SETTING FLYWHEEL ADAPTATION USING VOLVO SYSTEM TESTER

For an example of screen display during testing (Scheme 33)

  1. Connect Volvo System Tester (VST).
  2. Using VST, access MONITOR TEST scroll list. Find FLYWHEEL STATUS and FLYWHEEL ADAPTIVE values. Display will read F ADAP, F ADAP B, F ADAP C, etc. Values will display as a percentage. Example: F ADAP=0.0XXX%
  3. Drive vehicle in 2nd or 3rd gear at engine speed of 2500-3500 RPM. Decelerate without using brake. Flywheel adaptive values should start to change on VST. Repeat process until values stop changing. FLYWHEEL STATUS should change to READY.
  4. Shut off engine and allow to cool below 120°F (49°C). This puts engine in range to perform TRIP driving cycle.

TRIP DRIVING CYCLE USING VOLVO SYSTEM TESTER (VST)

Note. The following information is from Volvo technical service bulletin No. 0059, Section 2, Group 23, dated July, 2002.

Note. Engine idle and drive times may be slightly longer than given time, but must be NO LESS than set amount.

  1. Connect VST and start engine. Test drive vehicle at engine speed of 1500-2000 RPM. Maintain engine RPM for 6 minutes.
  2. Stop vehicle and idle engine for 70 seconds. This allows ECM to check fuel trim adaptive functions.
  3. Test drive vehicle at engine speed of 1600-2000 RPM. Maintain engine RPM for 6 minutes.
  4. Stop vehicle and idle engine for 70 seconds. This allows ECM to check Secondary Air diagnosis functions.
  5. Test drive vehicle and reach at least 45 mph. Drive for 5 minutes with engine at 1800-2200 RPM.
  6. Stop vehicle and idle engine for 60 seconds. This allows ECM to check EVAP leakage diagnosis functions.
  7. Test drive vehicle and reach at least 45 mph. Drive for 4 minutes with engine speed of 1800-2200 RPM.
  8. Stop vehicle and idle engine for 60 seconds. NOTE: In order to set cycle flag for idle air diagnosis, engine must come to idle 7 times. Step 9 ensures this.
  9. Test drive vehicle at engine speed of 1800-2200 RPM. Stop vehicle and idle engine for 60 seconds. Repeat this step 3-4 times. This allows ECM to complete diagnosis of all systems. DO NOT shut engine off. NOTE: DO NOT shut off engine or entire TRIP cycle will have to be repeated.
  10. With engine still running, move gear selector to neutral position and apply parking brake. Ensure all diagnostics are complete using VST. Access DIAGNOSTIC CHECK menu. It will display TRIP COMPLETED if TRIP was successful. If 2 TRIP cycles have been completed, VST will also display READINESS=YES or NO. If not all diagnostic functions are complete, parts of TRIP cycle can be redone. If this is the case, see «RE-TESTING PARTS OF TRIP CYCLE USING VOLVO SYSTEM TESTER (VST)»(ref-15336-S04870074682004012900000) .

Connector A (Black)

  1. Turn ignition off. Turn off all power consuming equipment in vehicle. Using DVOM, measure resistance between ground and test box socket numbers 13 (A13), 28 (A28) and 42 (A42). Resistance should be approximately zero ohms on each test.
  2. If resistance is within specification, continue with diagnostic test where it was interrupted. If resistance is not within specification, go to next step.
  3. Check ground terminals for contact resistance and oxidation. Ground terminals are located at left-front fender well near air filter housing and in frame well near right-front head light. (Scheme 34) Repair as necessary. Check for open in ground circuits between engine compartment and ECM. Repair as necessary. Check for high resistance or open in engine to chassis ground strap. Repair as necessary. Verify repair by repeating procedure, starting with step 1.

Scheme 34

Scheme 34
Scheme 34

Connector B (Grey)

  1. Turn ignition off. Turn off all power consuming equipment in vehicle. Connect Engine Control Module (ECM). see scheme 3 Using DVOM, measure resistance between ground and test box probe socket No. 28 (B28). Resistance should be approximately zero ohms.
  2. If resistance reading is within specification, continue with DIAGNOSTIC TEST where it was interrupted. If resistance reading is not within specification, go to next step.
  3. Check for contact resistance and oxidation at ground terminals. Ground terminals are located at left-front fender well near air filter housing and in frame well near right-front head light. (Scheme 34) Repair as necessary. Check for open in ground circuits between engine compartment and ECM. Repair as necessary. Verify repair by repeating procedure, starting with step 1.

Fault Conditions

DTC P0100, DTC P0102 or DTC P0103/EFI 121 is stored if signal from mass air flow (MAF) sensor is lower than 0.2 V or more than 2.2 V at idling speed, or is outside its permitted range for engine speed (RPM) and throttle angle.

Possible Causes

Signal too high

  1. Short to supply in signal cable.
  2. Open circuit in cable to signal or power ground.
  3. Defective mass air flow (MAF) sensor.
  4. Contact resistance in terminals.

Signal too low

  1. Defective fuse 11B/2 (underhood fuse/relay box).
  2. Open circuit in signal or power cable.
  3. Short to ground in signal cable.
  4. Fresh air hose damaged or loose.
  5. Defective mass air flow (MAF) sensor.
  6. Contact resistance in terminals.

Substitute Values

  1. ECM uses engine speed (RPM) and throttle angle to determine load.
  2. Idle air trim adaptation disabled.
  3. Long-term fuel trim disabled.
  4. EVAP diagnostic disabled.

The ECM compares the signal from the mass air flow (MAF) sensor with the signal from the throttle position (TP) sensor. DTC EFI-355 is stored if

  1. Outside temperature exceeds 45°F (7°C)
  2. Car is lower than 7874 ft. (2400 m) above sea level
  3. Engine coolant temperature (ECT) exceeds 176°F (+80°C)
  4. Engine speed (RPM) exceeds 1800 RPM
  5. Mass air flow (MAF) sensor and throttle position (TP) sensor signals do not correspond for 19 seconds

Note. Not during active boost pressure control.

Substitute Value

  1. None
  1. Defective MAF sensor
  2. Defective throttle position (TP) sensor

DTC P0106, P0107 or P0108/EFI 422 is stored if ECM receives a signal from atmospheric pressure sensor corresponding to a height above sea level of over 6.500 m (low signal) or under 780 m (high signal). DTC is stored if signal is unstable for 25 seconds (sporadic signal).

Signal too high

  1. Short to supply in signal cable.
  2. Open circuit in signal cable or ground lead.
  3. Short to supply in power cable.
  4. Contact resistance in terminals.
  5. Short to supply in A/C pressure sensor power cable.
  6. Short to supply voltage in fuel tank pressure sensor power cable.
  7. Short to supply in accelerometer power cable.
  8. Defective atmospheric pressure sensor.

Signal too low

  1. Short to ground in signal cable.
  2. Short to ground in power cable.
  3. Open circuit in power cable.
  4. Contact resistance in terminals.
  5. Short to ground in A/C pressure sensor.
  6. Short to ground in fuel tank pressure sensor power cable.
  7. Short to ground in accelerometer power cable.
  8. Defective atmospheric pressure sensor.
  9. Defective A/C pressure sensor.
  10. Defective fuel tank pressure sensor.
  11. Defective accelerometer.

Signal sporadic

  1. Loose connections.
  2. Contact resistance in terminals.
  3. Defective atmospheric pressure sensor.
  4. Defective A/C pressure sensor.
  5. Defective fuel tank pressure sensor.
  6. Defective accelerometer.

ECM assumes a height of 0 meters above sea level.

DTC EFI-251 is stored if the ECM receives a signal from the outside temperature sensor corresponding to a temperature below -49°F (-45°C) (signal too high), or higher than +284°F (+140°C) (signal too low) for more than 10 seconds. DTC EFI-251 is stored if the signal is instable for 25 seconds.

  1. ECM adopts an outside temperature of 68°F (20°C).

Possible Causes (Signal Too High)

  1. Open circuit in signal cable or ground lead
  2. Short circuit to supply voltage in signal cable
  3. Contact resistance in terminals
  4. Defective outside temperature sensor

Possible Causes (Signal Too Low)

  1. Short circuit to ground in signal cable
  2. Defective outside temperature sensor

Possible Causes (Signal Sporadic)

  1. Loose connections
  2. Contact resistance in terminals
  3. Defective outside temperature sensor

Fault Condition (Non-Turbo)

DTC EFI-123 is stored if the ECM receives a signal from the ECT sensor corresponding to a temperature lower than -47.2°F (44°C) (signal high) or higher than 298°F (148°C) (signal low). DTC EFI-123 is stored if the set time (depending on starting temperature) between the engine being started and it reaching 82.3°F (28°C) is exceeded.

Fault Condition (Turbo)

DTC EFI-123 is stored if the ECM receives a signal from the ECT sensor corresponding to a temperature lower than -47.2°F (44°C) (signal high) or higher than 298°F (148°C) (signal low). As soon as the engine is started the temperature is calculated theoretically. When the calculated ECT has reached 167°F (75°C) it is compared with the temperature from the ECT sensor. DTC EFI-123 is stored if the ECT sensor signal corresponds to a temperature lower than 136°F (58°C).

Substitute Value (Non-Turbo)

  1. At engine start, a substitute value of 68°F (20°C) is adopted, when the engine is running 181°F (83°C) is adopted.
  2. With ignition on the engine coolant fan operates at low-speed.
  3. When the engine is running the engine coolant fan operates at high-speed.
  4. When the engine is switched off the engine coolant fan runs on for 3 minutes.
  5. Idle air trim adaptation disabled.
  6. Long-term fuel trim disabled.
  7. Leakage diagnostic is turned off.

Substitute Value (Turbo)

  1. While vehicle is being driven, calculated engine coolant temperature is adopted.
  2. When vehicle is restarted, substitute value of 86°F (30°C) is adopted. When engine is started, engine coolant temperature is calculated theoretically.
  3. With ignition on, engine coolant fan operates at low-speed.
  4. While engine is running, engine coolant fan apertures at high-speed.
  5. With ignition off, engine coolant fan runs on for additional three minutes.
  6. Idle air trim adaptation disabled.
  7. Long-term fuel trim disabled.
  8. Leakage diagnostic is turned off.
  9. Initial boost pressure adopted.
  1. Short to voltage in signal circuit.
  2. Short to ground or open in signal circuit.
  3. Contact resistance in terminals.
  4. Defective engine coolant temperature sensor.
  1. Short to ground in signal circuit.
  2. Defective engine coolant temperature sensor.

Possible Causes (Faulty Signal)

  1. Defective engine coolant temperature sensor.
  2. Defective coolant thermostat.
  3. Contact resistance in terminals.
  4. Short to another cable in signal circuit.

DTC EFI-411 is stored if the ECM receives a signal from the throttle position (TP) sensor corresponding to a throttle angle of less than -3.3° (0.1 V) (signal too low), or greater than 100.1° (4.9 V) (signal too high).

  1. Idle air trim disabled
  2. Throttle angle set at 32.2°
  3. ECM uses the mass air flow (MAF) sensor signal to determine idling position
  4. ECM uses the mass air flow (MAF) sensor signal and engine speed (RPM) to determine full-load position
  5. Leakage diagnostic is disabled
  6. Pulsed secondary air injection (PAIR) diagnostic disabled
  1. Short circuit to supply voltage in power or signal cable
  2. Open circuit in signal cable or ground lead
  3. Contact resistance in terminals
  4. Defective throttle position (TP) sensor
  1. Short circuit to ground in power or signal cable
  2. Open circuit in power cable
  3. Contact resistance in terminals
  4. Defective throttle position (TP) sensor

Before fuel trim starts the front heated oxygen sensor (HO2S) must be ready. It should be at operational temperature and have the correct output voltage. Monitoring of the heated oxygen sensor (HO2S) function starts approximately 3 minutes after heated oxygen sensor (HO2S) heating starts. DTC EFI-212 is stored if there is a fault in the front or rear heated oxygen sensors (HO2S) or their cabling that affects the output voltage from the front heated oxygen sensor (HO2S).

  1. Fuel trim disabled
  2. Three-way catalytic converter (TWC) diagnostic disabled
  1. Short circuit to supply voltage in front heated oxygen sensor (HO2S) signal cable (+)
  2. Short circuit to supply voltage in front heated oxygen sensor (HO2S) signal cable (-)
  3. Short circuit to supply voltage in rear heated oxygen sensor (HO2S) signal cable (+)
  4. Short circuit to supply voltage in rear heated oxygen sensor (HO2S) signal cable (-)
  5. Defective front heated oxygen sensor (HO2S)
  6. Defective rear heated oxygen sensor (HO2S)
  1. Short circuit to ground in front heated oxygen sensor (HO2S) signal cable (+)
  2. Short circuit to ground in front heated oxygen sensor (HO2S) signal cable (-)
  3. Short circuit to ground in rear heated oxygen sensor (HO2S) signal cable (+)
  4. Short circuit to ground in rear heated oxygen sensor (HO2S) signal cable (-)
  5. Defective front heated oxygen sensor (HO2S)
  6. Defective rear heated oxygen sensor (HO2S)

Possible Causes (Signal

  1. Open circuit in signal cable (+)
  2. Open circuit in signal cable (-)
  3. Defective front heated oxygen sensor (HO2S)

The ECM continuously monitors the time (period 3.3 seconds) it takes for the HO2S to switch from rich to lean and back to rich again. If this time is too long, the ECM interprets this as a fault in the front heated oxygen sensor (HO2S) and DTC EFI-435 is stored.

  1. Twin heated oxygen sensor (HO2S) control disabled
  2. Pulsed secondary air injection (PAIR) diagnostic disabled

The rear heated oxygen sensor (HO2S) constantly monitors the front heated oxygen sensor (HO2S), ensuring that it adjusts the short term fuel trim integrator so that it corresponds to the exhaust gas oxygen content. If the short term fuel trim integrator deviates, the rear heated oxygen sensor (HO2S) will make fine adjustments to it. If this adjustment is too great the ECM interprets this as a damaged front heated oxygen sensor (HO2S) and DTC EFI-436 is stored.

  1. Twin heated oxygen sensor (HO2S) control disabled
  1. Uneven compression
  2. Air leakage in the intake system
  3. Air leakage in the exhaust system
  4. Defective rear heated oxygen sensor (HO2S)
  5. Defective front heated oxygen sensor (HO2S)

Monitoring of the heated oxygen sensor (HO2S) heating circuit begins approximately 3 minutes after the HO2S heating sequence starts. DDTCs EFI-521 or EFI-522 are stored if the ECM registers too high or low a current in the heating circuit.

  1. 2-heated oxygen sensor (HO2S) control disabled
  1. Short circuit to supply voltage in signal cable
  2. Defective heated oxygen sensor (HO2S)
  1. Short circuit to ground in signal cable
  2. Defective fuse 11B/5 (underhood fuse/relay box)
  3. Open-circuit in signal or power cable
  4. Contact resistance in terminals
  5. Defective heated oxygen sensor (HO2S)

The rear heated oxygen sensor (HO2S) must be at operating temperature and have the correct output voltage to affect fuel trim and monitor the three-way catalytic converter (TWC) and front heated oxygen sensor (HO2S). Monitoring of the heated oxygen sensor (HO2S) function starts approximately 3 minutes after heated oxygen sensor (HO2S) heating starts. DTC EFI-153 is stored if there is a fault in the front or rear heated oxygen sensors (HO2S) or their cabling that affects the output voltage from the rear heated oxygen sensor (HO2S).

  1. Twin heated oxygen sensor (HO2S) control disabled
  2. Three-way catalytic converter (TWC) diagnostic disabled
  1. Short circuit to supply voltage in front heated oxygen sensor (HO2S) signal cable (+)
  2. Short circuit to supply voltage in front heated oxygen sensor (HO2S) signal cable (-)
  3. Short circuit to supply voltage in rear heated oxygen sensor (HO2S) signal cable (+)
  4. Short circuit to supply voltage in rear heated oxygen sensor (HO2S) signal cable (-)
  5. Defective front heated oxygen sensor (HO2S)
  6. Defective rear heated oxygen sensor (HO2S)
  1. Short circuit to ground in front heated oxygen sensor (HO2S) signal cable (+)
  2. Short circuit to ground in front heated oxygen sensor (HO2S) signal cable (-)
  3. Short circuit to ground in rear heated oxygen sensor (HO2S) signal cable (+)
  4. Short circuit to ground in rear heated oxygen sensor (HO2S) signal cable (-)
  5. Defective front heated oxygen sensor (HO2S)
  6. Defective rear heated oxygen sensor (HO2S)

Possible Causes (Signal Missing)

  1. Open circuit in signal cable (+)
  2. Open-circuit in signal cable (-)
  3. Defective rear heated oxygen sensor (HO2S)

The rear heated oxygen sensor (HO2S) constantly monitors the front heated oxygen sensor (HO2S), ensuring that it adjusts the short term fuel trim integrator so that it corresponds to the exhaust gas oxygen content. If the short term fuel trim integrator deviates, the rear heated oxygen sensor (HO2S) will make fine adjustments to it. While the engine is running this adjustment can be both positive and negative. If the adjustment is only positive or negative the ECM interprets this as a damaged rear heated oxygen sensor (HO2S) and EFI-425 is stored.

  1. Twin heated oxygen sensor (HO2S) control disabled
  1. Uneven compression
  2. Air leakage in the intake system
  3. Air leakage in the exhaust system
  4. Faulty fuel and residual pressure
  5. Defective rear heated oxygen sensor (HO2S)

The ECM receives information from the Heated Oxygen Sensor (HO2S) about the fuel/air mixture in the idling and partial load ranges. If the fuel/air mixture deviates from lambda=1, the short-term fuel trim will compensate for this by adjusting injection time so that lamda=1 is achieved. When the short-term fuel trim makes an adjustment, the integrator median must be adjusted by the long-term trim. If adaptation needs to adjust to close to its maximum DTC EFI-232 (idling range -0.48 ms to +0.40 ms) or DTC EFI-231 (part load range factor 0.773-1.227) and the status message Upper limit (lean fuel/air mixture) or Lower limit (rich fuel/air mixture) will be stored.

  1. None

Possible Causes (Upper Limit)

  1. Defective mass air flow (MAF) sensor
  2. Low fuel pressure
  3. Air leakage
  4. Faulty sensor signals

Possible Causes (Lower Limit)

  1. Defective mass air flow (MAF) sensor
  2. High fuel pressure
  3. Leaking fuel injectors
  4. Leaking evaporative emission (EVAP) system
  5. Contaminated engine oil
  6. Oil level too high
  7. Faulty sensor signals

The DTC for that injector is stored if there is a short-circuit to ground/supply voltage or if there is an open-circuit in an injector circuit.

  1. Idle air trim disabled
  2. Fuel trim disabled
  1. Short circuit to supply voltage in signal cable
  2. Defective injector
  1. Short circuit to ground in signal cable
  1. Defective fuse 11B/2 (underhood fuse/relay box)
  2. Open circuit in signal or power cable
  3. Contact resistance in terminals
  4. Defective injector

DTC EFI-242 is stored if there is a short circuit to ground/voltage or an open circuit in the turbocharger (TC) control valve circuit.

  1. Short circuit to supply voltage in signal cable
  2. Defective turbocharger (TC) control valve
  1. Short circuit to ground in signal cable
  2. Defective turbocharger (TC) control valve
  1. Defective fuse 11B/5 (Underhood fuse/relay box)
  2. Open circuit in signal or power cable
  3. Contact resistance in terminals
  4. Defective turbocharger (TC) control valve

The ECM derives boost pressure from the mass air flow (MAF) sensor signal. DTC EFI-414 is stored if the ECM registers that the mass air flow (MAF) sensor is fault-free and the load signal exceeds a certain level.

  1. The system only permits initial boost pressure.
  1. Defective mass air flow (MAF) sensor
  2. Contact resistance in terminals
  3. Open-circuit in cable for boost pressure reduction from AW 50-42 (Auto. Trans.)
  4. Blocked hoses between turbocharger and turbocharger control valve or turbocharger control valve and pressure servo
  5. Defective turbocharger control valve
  6. Defective boost pressure control valve pressure servo
  7. Contact resistance in connectors

The DTC for that injector is stored if there is a short-circuit to ground/supply voltage or if there is an open-circuit in an injector circuit.

  1. Short circuit to supply voltage in signal cable
  2. Defective injector
  1. Short circuit to ground in signal cable
  1. Open circuit in signal or power cable
  2. Contact resistance in terminals
  3. Defective injector
  1. Defective spark plugs, ignition cables, distributor cap/rotor, ignition coil or flywheel/pulse wheel
  2. Blocked/leaking injector
  3. Uneven compression
  4. Leakage between cooling system and cylinder
  5. Moisture, flashover in ignition system secondary side
  6. Intermittent open circuit , intermittent short-circuit to ground
  7. Intermittent short circuit to voltage supply
  8. Contact resistance or loose connection in ignition system low-tension side, in injector circuit or fuel pump circuit
  9. Engine oil level too high
  10. Air leakage
  11. Fuel pressure and residual pressure incorrect

If engine temperature exceeds 104°F (40°C), engine speed exceeds 2500 RPM, load exceeds 3.0 ms and the signal from the knock sensor is missing for 4 seconds, the DTC for that knock sensor (KS) is stored.

  1. Kock control is disabled
  2. Ignition retarded for safety reasons
  3. Initial boost pressure adopted (turbocharged engines only)
  1. Short circuit to ground in signal cable
  2. Open circuit in signal cable or ground lead
  3. Contact resistance in terminals
  4. Defective knock sensor

DTC EFI-131 is stored if the ECM does not receive a signal from the engine speed (RPM) sensor for 10 engine revolutions.

Note. The polarity of the engine speed (RPM) sensor wiring is reversed in cars with a manual transmission with drilled holes in the flywheel rather than milled slots.

  1. No fuel injection or ignition
  1. Open circuit in signal cable or ground lead
  2. Short circuit to ground or supply voltage in signal cable
  3. Contact resistance in terminals
  4. Defective engine speed (RPM) sensor

DTC) EFI-214 is stored if the ECM counts more than two teeth too few or too many on the carrier plate/flywheel for two consecutive crankshaft revolutions, and this fault occurs at least three times in one trip.

Note. The polarity of the engine speed (RPM) sensor wiring is reversed in cars with a manual transmission with drilled holes in the flywheel rather than milled slots.

  1. None
  1. Loose contact in the wiring or connections
  2. Cable insulation damaged
  3. Contact resistance in terminals
  4. Damage to carrier plate/flywheel
  5. Defective engine speed (RPM) sensor

If the ECM does not receive any signal from the camshaft position (CMP) sensor for 2.4 engine revolutions, DTC EFI-314 is stored after 1 second when the next attempt to start the engine is made.

  1. On engine start, fuel injection and ignition are absent.
  1. Short circuit to ground or supply voltage in signal cable
  2. Open circuit in signal cable, power cable or ground lead
  3. Contact resistance in terminals
  4. Defective camshaft position (CMP) sensor

PAIR injection system (PAIR) is checked by disabling long-term fuel trim and canister purge (CP) valve control. ECM then checks short-term fuel trim integrator. If it is at maximum DTC P0410/EFI 442 (PAIR) is stored. PAIR pump can be heard operating continuously when DTC is set.

Setting of DTC 446 (PAIR valve leakage) and/or DTC 448 (PAIR pump, flow too low).

DTC P0410/EFI 445 is stored if there is a short to ground, short to supply voltage or open in PAIR injection system pump signal circuit.

  1. PAIR injection system diagnostic disabled.
  2. Front and rear heated oxygen sensor diagnostic disabled.
  3. Fuel trim disabled.

Possible Source (Signal Too High)

  1. Short to supply voltage in signal circuit.
  2. Defective PAIR injection system pump relay.

Possible Source (Signal Too Low)

  1. Open in signal cable or power cable circuit.
  2. Short to ground in signal circuit.
  3. Contact resistance in terminals.
  4. Defective PAIR injection system pump relay.

The PAIR injection system pump valve is checked by disabling the long-term fuel trim and canister purge valve control. The PAIR injection system pump is started and the PAIR injection system pump valve is kept closed, if the short-term fuel trim integrator rises above a set value within 6 seconds DTC 446 is stored.

Fuel trim is disabled.

If DTC 446 is set with DTC 442, possible causes are

  1. Leaking PAIR injection system valve
  2. Defective PAIR injection system solenoid valve
  3. Air leakage in the exhaust system

If DTC 448 is set with DTC 442, possible causes are

  1. PAIR injection system pump runs continuously
  2. Air leakage in the exhaust system
  3. Damage/hole in the hose between PAIR injection system pump and PAIR injection system valve

Fault Condition

The PAIR injection system pump is checked by disabling the long-term fuel trim and canister purge valve control. The PAIR injection system pump is started and the PAIR injection system valve is opened. If the short-term fuel trim integrator does not rise above a set value within 6 seconds DTC 448 is stored.

Fuel trim disabled.

Possible Causes (Flow Too High)

DTC is always stored together with DTC 442: PULSED SECONDARY AIR INJECTION SYSTEM - FLOW TOO HIGH and DTC 446 PULSED SECONDARY AIR INJECTION SYSTEM VALVE - LEAKAGE.

Possible Causes (Flow Too Low)

  1. Defective PAIR injection system valve
  2. Defective PAIR injection system pump relay
  3. Defective PAIR injection system pump
  4. Defective PAIR injection system solenoid valve
  5. Vacuum hoses or check valve blocked
  6. PAIR injection system air hoses/pipes blocked
  7. Open in circuit in PAIR injection system pump power cable or ground lead

DTC 447, PAIR injection system solenoid valve signal will be stored 5 seconds after the engine is started if there is a short in circuit to ground/supply voltage or an open in circuit in the solenoid valve signal cable.

Substitute Valve

PAIR injection system (PAIR) diagnostic disabled - front and rear heated oxygen sensor (HO2S) diagnostic disabled - fuel trim disabled

Short in circuit to supply voltage in signal cable or defective PAIR injection system solenoid valve

Short in circuit to ground in signal cable

  1. Defective fuse 11B/5
  2. Open in circuit in signal or power cable
  3. Contact resistance in terminals
  4. Defective PAIR injection system solenoid valve

The ECM continuously monitors three-way catalytic converter (TWC) efficiency by comparing the signal from the rear heated oxygen sensor (HO2S) with the signal from the front heated oxygen sensor (HO2S). When three-way catalytic converter (TWC) efficiency deviates too much the ECM stores DTC EFI-443.

  1. None
  1. Uneven compression
  2. Air leakage in the intake system
  3. Air leakage in the exhaust system
  4. Faulty fuel pressure
  5. Defective three-way catalytic converter (TWC)

The EVAP canister shut-off valve closes canister ventilation, the fuel tank system is now completely closed. If the pressure in the fuel tank drops below a set value, DTC EFI-315 (Canister purge valve, leakage) is stored.

  1. Twin heated oxygen sensor (HO2S) control disabled
  2. Pulsed secondary air injection (PAIR) diagnostic disabled
  1. Leaking canister purge (CP) valve

When the EVAP canister shut-off valve is closed, then the fuel tank system is closed. When the canister purge valve is pulsed, pressure in the fuel tank should drop rapidly. DTC P0442/EFI 611 is stored if pressure in fuel tank does not drop rapidly once EVAP canister shut-off valve is closed.

None

  1. Leaking fuel tank, filler pipe, fuel tank filler cap, EVAP canister, EVAP canister shut-off valve or lines between these components.
  2. Blocked Canister Purge (CP) valve, EVAP canister, fuel tank pressure sensor or pipes between these components.
  3. Sticking CP valve.
  4. Defective fuel tank pressure sensor.

When the EVAP canister shut-off valve is closed, then the canister purge valve is pulsed. When a specific vacuum has been achieved, the canister purge valve is closed. The vacuum in the fuel tank is allowed to stabilize. DTC P0445/EFI 612 is stored if pressure in fuel tank drops too much in a set period.

None

  1. Leaking fuel tank, filler pipe, fuel tank filler cap, EVAP canister, EVAP canister shut-off valve or lines between these components.
  2. Defective fuel tank pressure sensor.

DTC EFI-541 (Canister purge valve, signal) is stored if the ECM registers a fault in the canister purge (CP) valve coil or cables after 5 seconds.

  1. 2-heated oxygen sensor (HO2S) control disabled
  2. The electrical test of the front heated oxygen sensor (HO2S) is disabled
  3. The electrical test of the rear heated oxygen sensor (HO2S) is disabled
  4. The pulsed secondary air injection system (PAIR) test is disabled
  5. The heated oxygen sensor (HO2S) test is disabled
  6. The three-way catalytic converter (TWC) test is disabled
  7. Leak diagnostic disabled
  8. Fuel shut-off conditions changed
  1. Short circuit to supply voltage in signal cable
  2. Defective canister purge (CP) valve
  1. Short circuit to ground in signal cable
  1. Defective fuse 11B/5 (underhood fuse/relay box)
  2. Open-circuit in signal or power cable
  3. Defective canister purge (CP) valve

TheEVAP canister shut-off valve is open and the fuel tank system is vented. The canister purge valve is pulsed and because of the vacuum in the intake manifold, the engine draws air through the EVAP canister. Because the EVAP canister shut-off valve is open, the pressure in the fuel tank will start to drop slowly. DTC P0446/EFI 614 is stored if pressure in fuel tank drops too rapidly because EVAP canister shut-off valve is open.

None

  1. Blocked/sticking EVAP canister shut-off valve.
  2. Blocked EVAP canister shut-off valve filter.
  3. Blocked hose between EVAP canister and EVAP canister shut-off valve.
  4. Blocked hose between EVAP canister shut-off valve and filter.
  5. Blocked EVAP canister shut-off valve hose connection.
  6. Leaking canister purge valve.
  7. Fuel tank pressure sensor transmits a steady signal lower than -0.14 psi (-1000 Pa).

Fault Causes

DTC P0447/EFI 616 and DTC P0448/EFI 616 are stored if ECM registers a fault in EVAP canister shut-off valve coil or wiring.

Leakage diagnostic is disabled.

  1. Short to supply voltage signal circuit.
  2. Defective EVAP canister shut-off valve.
  1. Short to ground in signal circuit.
  1. Open circuit in signal or power circuit.
  2. Defective EVAP canister shut-off valve.

DTC P0450/EFI 621, DTC P0451/EFI 621, DTC P0452/EFI 621 or DTC P0453/EFI 621 is stored if ECM receives a signal from tank pressure sensor corresponding to pressure above 0.3 psi (2.05 kPa) or below -0.45 psi (-3.10 kPa), or if signal is sporadic for 25 seconds.

Leakage diagnostic is disabled.

  1. Short to supply voltage in signal circuit.
  2. Open in signal circuit or ground lead.
  3. Contact resistance in terminals.
  4. Defective fuel tank pressure sensor.
  1. Short to ground in signal circuit.
  2. Open in power circuit.
  3. Short to ground in A/C pressure sensor circuit.
  4. Short to ground in accelerometer power circuit.
  5. Short to ground in power circuit.
  6. Contact resistance in terminals.
  7. Defective fuel tank pressure sensor.
  8. Defective A/C pressure sensor.
  9. Defective atmospheric pressure sensor.
  10. Defective accelerometer.
  1. Loose connections.
  2. Contact resistance in terminals.
  3. Defective A/C pressure sensor.
  4. Defective acclerometer.
  5. Defective fuel tank pressure sensor.

DTC EFI-311 is stored if engine speed (RPM) exceeds 3330 RPM, internal load signal is above 6.5 ms and road speed is below 2 km/h for 7.5 seconds.

  1. ECM assumes 0 km/h
  2. EVAP leakage diagnostic is disabled
  1. Short circuit to ground or supply voltage in signal cable
  2. Open-circuit in signal cable
  3. Contact resistance in terminals
  4. Defective speedometer
  5. Fault in circuit between ABS control module and combined instrument panel

Scheme 35

Scheme 35: Diagnosis
Scheme 35: Diagnosis

Scheme 36

Scheme 36
Scheme 36
  1. Test drive vehicle. Using Volvo Scan Tool (998-8686), read off VSS signal. If speed is zero MPH, fault is permanent. Go to next step. If speed is okay, fault is intermittent. Check for ABS and instrument cluster DTCs. See INSTRUMENT PANEL article in ACCESSORIES/SAFETY EQUIPMENT section and «ANTI-LOCK BRAKE SYSTEM - WITH TRACTION CONTROL»(ref-125015) article BRAKES section.
  2. Test drive vehicle and ensure speedometer functions. If speedometer shows zero mph, speedometer or one of its components is defective. If speedometer is okay, determine if speedometer is VDO or Yazaki type. VDO type has odometer below speedometer needle. Yazaki type has odometer above speedometer needle. see scheme 28and see scheme 29. If speedometer is VDO, go to next step. If speedometer is Yazaki, go to step 4.
  3. Turn ignition on. Check if DTC 131 is stored. If DTC 131 is stored, check wiring between instrument cluster connector terminal A7 and ECM connector terminal B18 for a short circuit to voltage. If DTC 131 is not stored, go to next step.
  4. Connect test box between ECM and ECM connector. Shift transmission to Neutral. Raise and support front of vehicle. Turn ignition on. Measure voltage between test box pins No. 18 and 28. Rotate front wheels. If voltage varies between.5-12 volts, source of DTC is poor contact in ECM connector. Repair as necessary. If voltage is a steady reading of approximately zero volts, check for instrument cluster DTCs. If voltage is a steady reading of more than 5 volts on VDO speedometer, check for instrument cluster DTCs. See INSTRUMENT PANEL article in ACCESSORIES/SAFETY EQUIPMENT section and «ANTI-LOCK BRAKE SYSTEM - WITH TRACTION CONTROL»(ref-125015) article BRAKES section. On Yazaki speedometer, go to next step.
  5. Turn ignition off. Connect a test light between test box pins No. 18 and 28. Turn ignition on. If test light comes on, check wiring between instrument cluster connector terminal A7 and ECM connector terminal B18 for a short to voltage. If test light does not come on, check wiring between instrument cluster connector terminal A7 and ECM terminal B18 for an open circuit.

DTC EFI-233 is stored when the air mass through the valve increases or decreases too much, in order to hold the correct idling speed. The permitted range for idle air trim adaptation is between +22 kg/h (upper limit) and -8 kg/h (lower limit).

  1. None
  1. Blocked air cleaner or air intake
  2. Contact resistance in terminals
  3. Incorrectly adjusted throttle body
  4. Defective idle air control (IAC) valve
  1. Air leakage
  2. Contact resistance in terminals
  3. Incorrectly adjusted throttle body
  4. Defective idle air control (IAC) valve

DTC EFI-225 (A/C pressure sensor, signal) is stored if the ECM receives a signal from the A/C pressure sensor corresponding to a pressure above about 450 psi (31 bar) (signal high), or below about -1.2 psi (-0.08 bar) (signal low). When the engine is started with an engine temperature below 104°F (40°C), A/C pressure should rise by at least 13.5 psi (95 kPa) within 8 seconds. DTC EFI-225 (faulty signal) is stored if pressure does not rise sufficiently.

  1. ECM adopts a substitute value of 1.9 psi (13.5 kPa) when the A/C compressor is running
  2. Engine cooling fan runs at low-speed
  1. Short circuit to supply voltage in the signal cable
  2. Open-circuit in signal or ground cable
  3. Contact resistance in terminals
  4. Defective air conditioning (A/C) pressure sensor
  1. Short circuit to ground in signal cable
  2. Defective fuse
  3. Open circuit in power cable
  4. Short circuit to ground in power cable
  5. Short circuit to ground in fuel tank pressure sensor power cable
  6. Short circuit to ground in atmospheric pressure sensor power cable
  7. Short circuit to ground in accelerometer power cable
  8. Defective fuel tank pressure sensor
  9. Defective atmospheric pressure sensor
  10. Defective accelerometer
  11. Defective air conditioning (A/C) pressure sensor
  1. Defective air conditioning (A/C) pressure sensor
  2. Incorrect pressure in air conditioning (A/C) system
  3. Open-circuit in signal cable between pressure switch (Pressostat) and A/C compressor
  4. Defective solenoid clutch/compressor

DTC EFI-225 (A/C pressure sensor, signal) is stored if the ECM receives a signal from the A/C pressure sensor corresponding to a pressure above about 450 psi (31 bar) (signal high), or below about -1.2 psi (-0.08 bar) (signal low). When the engine is started with an engine temperature below 104°F (40°C), A/C pressure should rise by at least 13.5 psi (95 kPa) within 8 seconds. DTC EFI-225 (faulty signal) is stored if pressure does not rise sufficiently.

  1. ECM adopts a substitute value of 1.9 psi (13.5 kPa) when the A/C compressor is running
  2. Engine cooling fan runs at low-speed
  1. Short circuit to supply voltage in the signal cable
  2. Open-circuit in signal or ground cable
  3. Contact resistance in terminals
  4. Defective air conditioning (A/C) pressure sensor
  1. Short circuit to ground in signal cable
  2. Defective fuse 11B/5 (underhood fuse/relay box)
  3. Open circuit in power cable
  4. Short circuit to ground in power cable
  5. Short circuit to ground in fuel tank pressure sensor power cable
  6. Short circuit to ground in accelerometer power cable
  7. Defective air conditioning (A/C) pressure sensor
  1. Defective air conditioning (A/C) pressure sensor
  2. Incorrect pressure in air conditioning (A/C) system
  3. Open-circuit in signal cable between pressure switch (Pressostat) and A/C compressor
  4. Defective solenoid clutch/compressor

DTC EFI-131 is stored if the ECM does not receive a signal from the engine speed (RPM) sensor for 10 engine revolutions.

Note. The polarity of the engine speed (RPM) sensor wiring is reversed in cars with a manual transmission with drilled holes in the flywheel rather than milled slots.

  1. No fuel injection or ignition
  1. Open circuit in signal cable or ground lead
  2. Short circuit to ground or supply voltage in signal cable
  3. Contact resistance in terminals
  4. Defective engine speed (RPM) sensor

DTC EFI-132 is stored if battery voltage is lower than 8 V (signal too low) or higher than 16 V (signal too high) after the engine has started.

  1. EVAP leakage diagnostic is turned off
  2. Heated oxygen sensor (HO2S) aging diagnostic disabled
  3. Pulsed secondary air injection (PAIR) diagnostic disabled
  1. Charging system does not charge or overcharges
  2. Poor battery
  3. Contact resistance in terminals

DTC EFI-132 is stored if battery voltage is lower than 8 V (signal too low) or higher than 16 V (signal too high) after the engine has started.

  1. Leakage diagnostic is turned off
  2. Heated oxygen sensor (HO2S) aging diagnostic disabled
  3. Pulsed secondary air injection (PAIR) diagnostic disabled
  1. Charging system does not charge or overcharges
  2. Poor battery
  3. Contact resistance in terminals

DTC EFI-112 is stored if the ECM detects a fault in the ROM/EPROM memory circuits, ECM, temperature sensor circuit, knock control circuit (zero test, short term fuel trim test) or engine coolant temperature (ECT) sensor circuit NTC switch.

Substitute Value (Fault in ROM/EPROM Memory Circuit, ECM Temperature Sensor Circuit

  1. No substitute value
  2. Temperature sensor engine coolant fan low-speed

Substitute Value (Fault in Engine Coolant Temperature (ECT) Sensor Circuit NTC Switch

  1. When the engine is started a substitute value of 68°F (20°C) is adopted, after the engine has been running for a short time a value of 181°F (83°C) is adopted.
  2. Engine cooling fan starts running at low-speed
  3. Idle air trim adaptation disabled
  4. Long-term fuel trim disabled
  1. Fault in ECM, ROM/EPROM circuits
  2. Fault in ECM temperature sensor circuit
  3. Fault in ECM knock control circuit
  4. Fault in ECM engine coolant temperature (ECT) sensor circuit (NTC switch)

If the ECM senses that the DC signal from the accelerometer has changed its mean setting (2.5 V) to more than 3.5 V or less than 1.5 V, DTC EFI-444 is stored.

  1. None
  1. Short circuit to supply voltage in signal cable
  2. Open-circuit in signal cable, ground lead or power cable
  3. Short circuit to ground or supply voltage in power cable
  4. Contact resistance in terminals
  5. Short circuit to ground in air conditioning (A/C) pressure sensor
  6. Short circuit to ground in fuel tank pressure sensor power cable
  7. Short circuit to ground in atmospheric pressure sensor power cable
  8. Defective air conditioning (A/C) pressure sensor
  9. Defective atmospheric pressure sensor
  10. Defective fuel tank pressure sensor
  11. Defective accelerometer
  1. Short circuit to ground in signal cable
  2. Defective accelerometer

Fault Conditions (EFI 432)

DTC EFI-432 is stored if the temperature in the control module exceeds 212°F (100°C).

Fault Conditions (EFI 513)

DTC EFI-513 is stored in addition to DTC EFI-432 if temperature in the control module exceeds 230°F (110°C).

  1. Engine cooling fan starts running at low-speed
  1. Engine cooling fan does not work
  2. Air supply blocked

DTC EFI-223/EFI-245 is stored if the ECM registers a fault in the cable from the idle air control (IAC) valve opening/closing coil.

  1. Idle air trim disabled
  2. Fuel shut-off conditions changed
  3. Output signals to the coils are regulated with a fixed value depending on the cause of the fault
  4. Leakage diagnostic is disabled
  1. Short circuit to supply voltage in the signal cable
  2. Defective idle air control (IAC) valve
  1. Opening and closing coil signal cables short-circuited to each other
  2. Defective fuse 11B/2 (underhood fuse/relay box)
  3. Open circuit in power cable
  4. Short circuit to ground in signal cable
  5. Defective idle air control (IAC) valve
  6. Contact resistance in terminals
  1. Open-circuit in signal cable
  2. Defective idle air control (IAC) valve
  3. Contact resistance in terminals

DTC EFI-534 is stored if the ECM registers a fault in the ignition coil, fuel pump, A/T load signal, MIL or engine cooling fan high speed circuits.

  1. The ignition discharge module is shut off until the fault has disappeared.
  1. Short circuit to supply voltage in ignition discharge module (IDM) signal cable
  2. Defective ignition discharge module (IDM)/ignition coil
  3. Short circuit to supply voltage in fuel pump relay signal cable
  4. Defective fuel pump relay
  5. Short circuit to supply voltage in Transmission Control Module (TCM) load signal cable
  6. Short circuit to supply voltage in MIL signal cable
  7. Short circuit to supply voltage in engine cooling fan high speed signal cable
  8. Defective engine cooling fan relay

DTC EFI 535 is stored if the ECM registers a fault in the A/C relay or pulsed secondary air injection system (PAIR) pump relay circuits.

  1. Ignition discharge module (IDM) is shut off until the fault disappears.
  1. Short circuit to supply voltage in A/C relay signal cable
  2. Defective A/C relay

The automatic Transmission Control Module (TCM) can request the lighting of the malfunction indicator lamp (MIL) by transmitting a signal to the ECM. DTC EFI-335 is stored if the ECM registers a fault in the signal cable. When the engine is started the ECM checks for a short-circuit to supply voltage or open-circuit (high signal) in the signal cable. When the engine is running, the ECM checks for a short-circuit to ground in the signal cable (low signal).

  1. None
  1. Open circuit in signal cable
  2. Short circuit to supply voltage in signal cable
  1. Short circuit to ground in signal cable

DTC EFI-514 is stored if there is a short circuit to ground/supply voltage or open-circuit in the engine cooling fan (FC) signal cable.

  1. Idle air trim disabled
  2. Fuel trim disabled
  3. Conditions for fuel shut-off changed
  4. If engine coolant temperature exceeds 215°F (102°C), the engine cooling fan (FC) starts operating at high-speed
  1. Short circuit to ground in signal cable (ECM terminal A7)
  2. Defective engine cooling fan (FC) relay
  1. Short circuit to ground in signal cable
  2. Defective engine cooling fan (FC) relay
  1. Open circuit in signal cable
  2. Open circuit in engine cooling fan (FC) relay power cable
  3. Short circuit to ground in signal cable (ECM terminal A22)
  4. Contact resistance in terminals
  5. Defective engine cooling fan (FC) relay

This DTC indicates whether there are one or more emission related DTCs stored in the Automatic Transmission Control Module (TCM). DTC EFI-666 is stored 2 seconds after the TCM requests malfunction indicator lamp (MIL) lighting from the Motronic 4.4 ECM.

None

One or more DTCs stored in Automatic Transmission Control Module (TCM).

EFI 533: IGNITION DISCHARGE MODULE GROUP C - HIGH

For connector terminal identification see scheme 14- see scheme 24 and ENGINE PERFORMANCE in appropriate SYSTEMS WIRING DIAGRAM article in ELECTRICAL as follows

  1. «SYSTEM WIRING DIAGRAMS - C70»(ref-118611)
  2. «SYSTEM WIRING DIAGRAMS - S70»(ref-119004)
  3. «SYSTEM WIRING DIAGRAMS - V70»(ref-119777)

For component locations, see

COMPONENT LOCATIONS

EFI 533 is stored if ECM registers short in ECM terminal B19 circuit.

Ignition discharge module is disabled until fault has disappeared.

  1. Short to voltage or ground in ECM terminal B19 circuit.
  2. Defective ECM.

SUMMARY

If no hard fault codes (or only pass codes) are present, driveability symptoms exist or intermittent codes exist, proceed to TESTS W/O CODESTESTS W/O CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.

More articles — Engine Controls - Tests W/codes