0503
Diagnostic Trouble Code 0503 indicates a problem with the front Oxygen Sensor on the right cylinder bank. The right bank is also called the rear bank. It is cylinders 1,3,5. A normal signal sweeps back and forth between 0.2 volts and 0.8 volts. This malfunction was detected when the Engine Control Module received a signal from the sensor which was a constant value of approximately 0.3 volts.
Possible causes include ...
- Harness or connectors (the sensor circuit is open or shorted).
- Defective Oxygen Sensor
0504
Diagnostic Trouble Code 0504 points to a problem with the Automatic Transmission Communications line. Pulse signals are exchanged between the Engine Control Module and the Transmission Control Module to assure smooth shifting during hard acceleration or deceleration.
This malfunction is detected when the ECM continuously receives an incorrect voltage from the TCM. Possible causes include...
- Harness or connectors (The communications line circuit between the ECM and the TCM is open or shorted.)
- TCM
- Discharged or faulty battery
0505
No Failure Recorded/Detected
0510
Diagnostic Trouble Code 0510 points to a problem with the Rear Heated Oxygen Sensor. This sensor is mounted in the exhaust stream, just downstream of the Catalytic Converter. When the two Front Heated Oxygen Sensors are operating properly the Rear Heated Oxygen Sensor is not used for engine control operation. It is used to monitor the condition of the Catalytic Converter. If either or both Front Sensors fail the Engine Control Module uses the signal from the Rear Sensor to maintain a correct fuel/air mixture.
DTC 0510 is detected when the signal from the Rear Heated Oxygen Sensor does not reach the expected maximum voltage threshold value. The possible causes include ...
- Harness or connectors (the sensor circuit is open or shorted.)
- Rear Heated Oxygen Sensor
- Fuel pressure
- Fuel injectors
- Intake air leaks
0603 0604 0605 0606 0607 0608
If one cylinder is misfiring the problem is spark or fuel. A misfire due to a spark problem usually results in a Service Engine Soon light and one of these Diagnostic Trouble Codes:
0608 - Cylinder 1 misfire
0607 - Cylinder 2 misfire
0606 - Cylinder 3 misfire
0605 - Cylinder 4 misfire
0604 - Cylinder 5 misfire
0603 - Cylinder 6 misfire
You don't have any of these codes, and the engine smooths out at engine speeds greater than 1000 rpm, so let's assume the problem is with fuel delivery.
I believe one of your fuel injectors is not performing properly. There are two tests the home mechanic can make, the sound test and the resistance test.
Sound test...
This test is performed with the engine idling. Use a mechanic's
s***hoscope or a length of rubber vacuum hose, and listen to each injector.
All injectors should sound alike. If you find one which makes a different
sound (or no sound at all) you have found a problem.
Resistance test...
This test is performed with the engine off. Use an ohmmeter to measure the
resistance of each injector. This does not require removing the injectors.
I don't know the correct resistance value for the injectors on your model,
but they are typically a low number such as 16 ohms. The important thing
is they should all be equal. If you find one injector with substantially
higher resistance than the others, it is bad. If you find one with zero
ohms (short circuit) that is truly unfortunate, because the injector is bad
and it may also have damaged the Engine Control Module (the computer)
because of excessive current drain.
Measuring the resistance of the front bank of cylinders is easy because the
injectors are in plain view. Disconnect the injector electrical connector
for cylinder #2, measure the resistance, reconnect the connector. Repeat
for the cylinders #4 and #6.
Measuring the resistance of the rear bank of cylinders is almost as easy,
but it is difficult to reach the injectors. The resistance may be measured
at a conveniently located electrical connector. Notice the largest,
thickest electrical harness at the top of the engine. This is the Engine
Control Harness and it is shaped like a U, with the open top of the U at the
driver's side of the car. The U has two corners. Look at the corner
nearest the passenger seat. Just inside that corner you will find an 8-pin
electrical connector. This is connector F131. Disconnect this
connector. Now look at the male part, the connector half with the pins
exposed. They are arranged in two rows of four pins.
The pins are numbered 1 - 4 (top row) and 5 - 8 (bottom row).
Measure the resistance of:
- injector #1 between pins 1 and 2.
- injector #3 between pins 1 and 6.
- injector #5 between pins 1 and 5.
Be sure to measure the PINS, not the female receptacles.
The dealer's shop is equipped with high-tech diagnostic instruments. These are wonderful devices but they are expensive and the dealer has to recover his cost by charging you for diagnostic time. Sometimes the home mechanic can do legitimate diagnostic work with nothing more than a ohmmeter and a
rubber tube.
To Test Ignition Coils:
With the ignition off, disconnect the electrical connector from the ignition coil. Connect the positive (+) probe of an ohmmeter to terminal no. 1 and the negative (-) probe to terminal no. 2 of the coil connector - the meter should indicate infinite resistance. Reverse the meter leads ( negative probe to terminal no. 1 and positive probe to terminal no.2) - the continuity should be indicated, but not zero ohms. If the results are not as specified, replace the coil.
Connect an ohmmeter between the secondary terminal ( the one that the spark plug connects to) and terminal no. 1 - the meter should indicate infinite resistance. If not, replace the coil.
Note - Ohm meter to test coils is not the most reliable way. Some peoples’ coils tested perfectly, but they still misfired.
0701
Engine won't Start Codes 0101..0303..0701..HLP
0702
Diagnostic Trouble Code 0702 points to a problem with the three-way Catalytic Converter.
The Cat is one of the principal components of the emissions control system. The Engine Control Module monitors the signals from the two front Oxygen Sensors and the one rear Oxygen Sensor. The signal frequency of each sensor indicates something about the condition of that sensor. A comparison of the frequency of the front sensors with the rear sensor indicates something about the condition of the Cat.
This malfunction was detected when the ratio of the signal frequency from the right bank front Oxygen Sensor to the signal frequency of the rear Oxygen Sensor exceeded a critical threshold value. This indicates that the Cat does not have enough oxygen storage capacity. The right cylinder bank is also called the rear bank. It is cylinders 1,3,5. Possible causes of this DTC include ...
- Three-way catalyst
- Exhaust tube
- Intake air leaks
- Fuel injectors
- Spark plugs
- Ignition timing
0703
Diagnostic Trouble Code 0703 points to a problem with the three-way Catalytic Converter.
The Cat is one of the principal components of the emissions control system. The Engine Control Module monitors the signals from the two front Oxygen Sensors and the one rear Oxygen Sensor. The signal frequency of each sensor indicates something about the condition of that sensor. A comparison of the frequency of the front sensors with the rear sensor indicates something about the condition of the Cat.
This malfunction was detected when the ratio of the signal frequency from the left bank front Oxygen Sensor to the signal frequency of the rear Oxygen Sensor exceeded a critical threshold value. This indicates that the Cat does not have enough oxygen storage capacity. Possible causes include ...
- Three-way catalyst
- Exhaust tube
- Intake air leaks
- Fuel injectors
- Spark plugs
- Ignition timing
0704
Diagnostic Trouble Code 0704 points to a problem with the Evaporative Emission Control System Pressure Sensor. The EVAPCSPS is installed in the purge line. The sensor detects the pressure inside the purge line and sends a signal to the Engine Control Module. The signal voltage is directly proportional to pressure. The EVAPCSPS is not directly used to control engine operating parameters. It is used only to evaluate EVAP performance. Therefore a car with DTC 0704 should start and run normally.
The EVAPCSPS is located on the underside of the car near the left rear wheel. It is mounted near, but not directly on, the EVAP canister.
This malfunction is detected when the EVAPCSPS sends an out-of-range voltage signal to the Engine Control Module.
Possible causes include...
- harness or connectors (The EVAPCSPS circuit is open or shorted.)
- bad EVAPCSPS
- EVAP Canister Vent Control Valve is stuck open
- rubber hose connected to EVAPCSPS is clogged, bent, kinked, disconnected, or improperly connected
- EVAP Canister is damaged or saturated with water
- rubber hose from EVAP Canister Vent Control Valve to the water separator
- EVAP Canister Purge Volume Control Solenoid Valve
0705
Diagnostic Trouble Code 0705 points to a problem with the Evaporative Emission Control System.
This malfunction is detected when the EVAP control system has a leak or the EVAP control system does not operate properly. (EVAP = EVAPorative emissions.)
Possible causes include...
- incorrect fuel tank vacuum relief valve
- incorrect fuel filler cap
- fuel filler cap vent remains open or fails to close
- foreign matter caught in fuel filler cap
- a leak in the line between the intake manifold and the
EVAP Canister Vacuum Control Valve
- foreign matter caught in the EVAP CVCV
- leaks in the EVAP canister or fuel tank
- leaks in the EVAP purge line (pipe and rubber tube)
- EVAP purge line rubber tube bent
- blocked or bent rubber tube to EVAP control system pressure sensor
- loose or disconnected rubber tube
- EVAP CVCV and circuit
- EVAP Canister Purge Volume Control Solenoid Valve and circuit
- absolute pressure sensor
- tank fuel temperature sensor
- MAP/BARO switch solenoid valve and circuit
- blocked or bent rubber tube to MAP/BARO switch solenoid valve
- O-ring of EVAP CVCV is missing or damaged
- water separator
- EVAP canister saturated with water
- EVAP control system pressure sensor
- refueling EVAP vapor cut valve
- ORVR system leaks
This is a "jackpot" DTC. It points to so many things you don't know what to check. It is often combined with another DTC which is more specific and therefore more helpful.
0707
Your Maxima engine is OBD-2 compliant. All Diagnostic Trouble Codes are four digits, with the first is always 0 or 1. Therefore your "77" is actually "0707" which points to the rear Oxygen Sensor.
Your Maxima has three Oxygen Sensors. Two are front sensors, mounted in
the Y-pipe between the exhaust manifolds and the Catalytic Converter. One
is a rear sensor, mounted in the exhaust pipe downstream of the Cat.
When both front Oxygen Sensors are operating normally the rear sensor serves only to keep tabs on the Catalytic Converter. That's the reason your engine is running well. The Engine Control Module (the computer) is not using the signal from the rear sensor to control engine management functions.
For more information about Oxygen Sensors go to
http://www.volksparts.com/o2sensors.htm
For specific information about replacing Oxygen Sensors on your Maxima see
the Chilton manual (page 4-13) or the Haynes manual (page 6-14).
In a different thread SprintMax said he got a great price on a replacement factory Oxygen Sensor from Vester Nissan. He didn't give a location or contact information. Perhaps he was referring to Vester Nissan of Clinton NC, 1-800-572-2005.
0801
Diagnostic Trouble Code 0801 points to a problem with the Vacuum Cut Valve Bypass Valve. The malfunction is detected when an improper voltage signal is sent to the Engine Control Module through the VCVBV. The possible causes of this problem include a defect with the wiring or electrical connector, or with the valve itself. The VCVBV is located under the car, near the rear left tire. It is near the Evaporative Emission Canister but not mounted directly on it.
The VCVBV is a solenoid-controlled air valve. You may remove it from the vehicle and perform a bench test. There are two air hose nipples on the valve. Fasten a length of clean rubber vacuum tubing to either nipple. Gently blow through the hose. The valve should be closed and it should be difficult or impossible to send air through the valve. Now use a pair of fused test leads to provide 12 volts to the electric connector. The polarity doesn't matter. With the VCVBV solenoid energized the valve should be open and it should be easy to send air through the valve.
0802
Thanks to OBD and The Org !
0803
Engine code
0804
Diagnostic Trouble Code 0804 is detected when the signal from the Transmission Control Module is not sent to the Engine Control Module. The factory service manual identifies these possible causes:
- Harness or connectors (the communications line circuit between ECM and TCM is open or shorted.)
- TCM
- Weak or dead battery
0806
http://forums.maxima.org/search.php?...der=descending
0807
Diagnostic Trouble Code 0807 does not appear in the '99 Maxima factory service manual, and that is my principal information source. I'll tell what I know about the '99 Maxima EVAP Canister Purge Volume Control Solenoid Valve. This information may or may not apply to your Maxima.
The Evaporative Emission (EVAP) Canister Purge Volume Control Solenoid Valve uses an on/off duty cycle to control the flow of fuel vapor from the EVAP canister. Diagnostic Trouble Code 1008 is set when the Engine Control Module (the computer) detects an improper signal through the valve. The problem is likely to be in the electrical wiring, harness, or the valve itself.
Check fuse #58 (10 amps) and replace if necessary.
The CPVCSV is easy to see and reach. It is located in the engine compartment, mounted to the top of the upper intake manifold. Notice the Vehicle Serial number stamped into the firewall. Put your finger on the third-from-last number. Move your finger three inches toward the radiator. That's the CPVCSV. It has one two-wire electrical connector and two vacuum hoses.
You may test the valve. This test procedure is performed with the engine off. Remove the electrical connector and both vacuum hoses. Fasten a length of clean rubber vacuum tubing to either nipple. Gently blow through the hose. The valve should be closed and it should be difficult or impossible to send air through the valve. Now use a pair of fused test leads to provide 12 volts to the electric terminals. The polarity doesn't matter. With the solenoid energized the valve should be open and it should be easy to send air through the valve.
0901
Diagnostic Trouble Code 0901 points to a problem with the Front Heated Oxygen Sensor, Right Bank. The right cylinder bank is also called the rear bank. It is cylinders 1,3,5.
The Front Heated Oxygen Sensors are installed in the Y-pipe, the part of the exhaust system which conveys exhaust gases from the exhaust manifolds to the Catalytic Converter. There is an Oxygen Sensor in each branch of the Y-pipe. These sensors produce a signal which varies with the concentration of oxygen in the exhaust gas, as compared to the outside air. This signal is sent to the Engine Control Module which uses it to control the fuel injection system.
DTC 0901 is detected when the current drawn by the heating element in the Oxygen Sensor is out of the normal range.
Possible causes include ...
- harness or connectors (the sensor circuit is open or shorted.)
- a defective Front Heated Oxygen Sensor (right bank).
The heated Oxygen Sensors have two components: a heating element and a sensing element. The heating element may be tested with an ordinary ohmmeter. This test is done with the engine off.
Follow the wires away from the Oxygen Sensor until you find the nearest electrical connector. Disconnect the connector. Viewed with the connector latch at the 12 o'clock position, there are three terminals. They are numbered 1-3, right to left. Be sure to measure the terminals in the connector half which is attached to the Oxygen Sensor, not the one which leads to the Engine Control Unit.
Measure the resistance between terminals 1 and 3.
The factory spec is 2.3-4.3 ohms at 77 degrees Fahrenheit.
Measure the resistance between terminals 1 and 2.
The reading should be infinity (no connection).
Measure the resistance between terminals 2 and 3.
The reading should be infinity (no connection).
If the resistance measurements are significantly different from the factory specifications the sensor is faulty and must be replaced.
If the resistance measurements meet the factory specifications the sensor may be good and the wiring is defective. You could exchange the two Front Heated Oxygen Sensors and reset the Engine Control Module. Then drive normally and expect the Malfunction Indicator Lamp to turn on again. If you still get DTC 0901 the wiring is faulty. If you get DTC 1001 the sensor is bad.
0902
Diagnostic Trouble Code 0902 points to a problem with the Rear Heated Oxygen Sensor Heater.
The malfunction is detected when the current in the Oxygen Sensor heater circuit is out of the normal range.
Possible causes include ...
- the electrical harnesses
- the connector
- the Oxygen Sensor heaters
You may test the heater with an ohmmeter. This test is done with the engine off.
Raise the car and support it on sturdy jackstands. Slide under and disconnect the connector. Viewed with the connector latch at the 12 o'clock position, there are four terminals. They are numbered 1-2, top row, right to left and 3-4, bottom row, right to left. Be sure to measure the resistances of the Oxygen Sensor, not the harness which leads to the Engine Control Unit.
Measure the resistance between terminals 1 and 4.
The factory spec is 2.3-4.3 ohms at 77 degrees Fahrenheit.
Measure the resistance between terminals 2 and each of the other terminals.
The reading should be infinity (no connection).
Measure the resistance between terminals 3 and each of the other terminals.
The reading should be infinity (no connection).
Check fuse #31 (15 amps) in the passenger cabin fuse block. That fuse block has three columns of fuses.
The left-most column contains fuses 1 - 11, numbered from bottom to top.
The middle column contains fuses 12 - 26, numbered from bottom to top.
The right-most column contains fuses 27 - 40, numbered from bottom to top.
The numbers are molded into the plastic fuse block. They are not easy to read. A flashlight will be helpful.