QuestionQUESTION: How do I manually retrieve codes on a 1994 Nissan Sentra LE (Limited Edition) 1.6 litre, 5 speed manual transmission. The access port is under the fuse panel on the driver's side, with ALDL connector. Is there a way to jumper the access point to access the codes?
Thank you,
Rick
ANSWER: Rick,
OBDII can be checked with a scanner for free at Autozone or Checker. Or, if you want Wal Mart has a great scanner for $68 bucks in the automotive section. I use a scanner on 1993 and newer and do not know if there is a way to check yours manually. If yours was a 1992 the manual way of checking the computer ECM using the screwdriver and flashing light would work. I do not think yours is so equipped.
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QUESTION: Hello, thank you for your reply. It is not an OBDII connector. It is ALDL. The ECM does not have an access hole. I have had it out to look at it, and there is nothing that resembles the usual way to get the codes.
The connector has straight sides, not the tapered sides of the OBDII connector. And, it does not have the tab that sticks out like the OBDI connector has. This is an ALDL connector.
Thank you!
Rick
ANSWER: Rick,
You are correct and I am wrong. Here is the procedure to check and reset codes pre-OBDII.
How to check for fault codes.
The ECCS Control is found under the passenger side kick panel.
The ECU has a window on one side to view a red LED and a green LED - when checking fault codes, a red flash is worth 10, and a green flash is worth 1. So for example, the code to say that everything is functioning normally would be 5 red flashes and 5 green flashes - the code is 55.
The ECU has 5 modes of operation, for diagnostics codes, it has to be set to mode 3.
1. Make sure the screw next to the viewing window is turned clockwise.
2. Turn the ignition on
3. Both LEDs with flash once, then a pause, then a second time, then a pause, etc. etc. up to 5 times then will repeat the process. After is has flashed 3 times then turn the screw completely anti-clockwise. - this will select mode 3.
4. The LEDs will now flash codes. 55 means that everything is normal. The rest are written below.
5. When finished, turn the screw back to clockwise and the ECU will reset itself automatically.
Don't worry about the '5th cylinder misfire' and '6th cylinder misfire' or anything, the codes are the same for all Nissans.
11 Crank Angle Sensor/Camshaft Position Sensor.
12 Air Flow Meter/Mass Air Flow Sensor.
13 Engine Coolant Temperature Sensor.
14 Vehicle Speed Sensor.
21 Ignition Signal.
22 Fuel Pump.
23 Idle Switch.
24 Throttle Valve Switch.
25 Idle Speed Control Valve.
28 Cooling Fan Circuit.
31 ECM.
32 EGR Function.
33 Heated Oxygen Sensor.
34 Knock Sensor.
35 Exhaust Gas Temperature Sensor.
36 EGR Control-Back Pressure Transducer.
37 Knock Sensor.
38 Right hand bank Closed Loop (B2).
41 Intake Air Temperature Sensor.
42 Fuel Temperature Sensor.
43 Throttle Position Sensor.
45 Injector Leak.
47 Crankshaft Position Sensor.
51 Injector Circuit.
53 Oxygen Sensor.
54 A/T Control.
55 No Malfunction.
63 No. 6 Cylinder Misfire.
64 No. 5 Cylinder Misfire.
65 No. 4 Cylinder Misfire.
66 No. 3 Cylinder Misfire.
67 No. 2 Cylinder Misfire.
68 No. 1 Cylinder Misfire.
71 Random Misfire.
72 TWC Function right hand bank.
73 TWC Function right hand bank.
76 Fuel Injection System Function right hand bank.
77 Rear Heated Oxygen Sensor Circuit.
82 Crankshaft Position Sensor.
84 A/T Diagnosis Communication Line.
85 VTC Solenoid Valve Circuit.
86 Fuel Injection System Function right hand bank.
87 Canister Control Solenoid Valve Circuit.
91 Front Heated Oxygen Sensor Heater Circuit right hand bank.
94 TCC Solenoid Valve.
95 Crankshaft Position Sensor.
98 Engine Coolant Temperature Sensor.
101 Front Heated Oxygen Sensor Heater Circuit right hand bank.
103 Park/Neutral Position Switch Circuit.
105 EGR and EGR Canister Control Solenoid Valve Circuit.
108 Canister Purge Control Valve Circuit
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QUESTION: Thank you for your very detailed reply. The ECM in this car does not have LEDs or a knob or screw that can be turned. The connector is located under the fuse panel on the driver's side. It just has the plug-in. The ECM itself is in the dash, behind and below the radio. There is no kick panel on the passenger side. I had to tear into the dash to get the ECM out. It has been a very frustrating experience trying to find this information, and I am grateful for your excellent effort trying to help me.
One other thing I can mention is that the codes have been accessed in the past by another mechanic, and somehow, he either used a wire and jumpered it, or he had some kind of connector that was designed for a different vehicle that worked on this car. If I could get a schematic of the plug, I might be able to find the ground wire and the other wire that I need to be used together to get the ECM to release the codes.
I tried a local Nissan dealership, asked them for the information, and the person I talked with said they couldn't give out that information because of "liability issues."
It seems this particular model of the Sentra is an oddball! It does say it's a Limited Edition, and this is probably why! ;-) The manufacturer date is August 1994, which should make it a 1995, but the EPA rating is 1994, and it's registered as a 1994. It is probably that way because Nissan did not make it OBDII compliant.
Again, thank you very much for your efforts to help resolve this problem.
Rick
AnswerRick,
Here is a site that has connectors to hook up to a laptop for reading OBDI ALDL connectors. I have a SnapOn Scan tool for an old Corvette I have that would work on yours since I have the import module. If you live in or close to Las Vegas you could stop by and get the codes read. Otherwise it is a matter of finding a shop with an old code reader. I bought mine off of ebay for $500 bucks.
