1986 Nissan Truck Sensor Light

Have you had the truck since it was new? I have gone through all the diagrams from '83 to '86 and your computer "is" supposed to have a red and green led. The single green led is apparently from an older model. If I remember correctly from years back, there is supposed to be a screw you have to run in or out to access the codes and the single green led blinks like the check engine light on a GM. Take another look and let me know.

Let me dig a little deeper and I'll try to get back to you yet today, Jim.

I haven't forgotten you. I need to access a part of my system for the older models and it is down right now. I'll keep trying.

Hi, I had one of those trucks so I cant help you, to run the codes you need to turn the key to the on position, then on the side of the comp there is a small switch or screw, this switch controls the "mode" the computer is in, after the switch is thrown one or both lights will flash, one, two, three, four blinks, when it gets to four throw the switch back, then it will flash you the codes, tens then ones, example, first light will flash "one" the second light flashes 4 times, code number 14. Turn the key of to return to normal mode. If your comp has a screw turn it for "on" then trun it back for off, please let me know how it goes. To clear code disconnect the battery for 5 mins.

:-)

I have checked every computer system for a nissan p/u from '80 to '87 and can find nothing on the type of computer you have. I've even checked some of the cars. I used to have a repair manual for just Nissan and Toyota car and truck computers up to '88, but I can't find it. Probably lent it out. I'll keep looking, the answer is here somewhere.

Thanks Jim, Does the ECU have a screw with an arrow?

Yes it does, Jim

That is the "switch" turn the screw one way turns the switch on, then back the other turns the switch off.

I hope this help this shows how the ecm should look like and is a removel and instal of ecm with all locations

GOOD
FLUSH WITH
EDGE OF COMPUTERMODEL LOCATION
240SX ALL D
280ZX ALL A
300ZX TO '89 D
300ZX 90+ C
TRUCK & PATHFINDER
86+
E
G20 ALL B
Q45 ALL ENG. = D TRANS =
SENTRA / 200SX 91+ B
MAXIMA 89+ B
NO GOOD
MUST BE FLUSH WITH
EDGE OF COMPUTER
COMPUTER (ECU)
 LOCATE THE ECU ON THE CHART BELOW.
 DISCONNECT THE BATTERY.
 UNBOLT THE ECU FROM THE VEHICLE AND USING A 10 M.M. SOCKET (SINGLE
CONNECTOR TYPE ONLY), DISCONNECT THE ELECTRICAL CONNECTOR.
 INSTALL NEW ECU IN REVERSE ORDER MAKING SURE THAT THE ELECTRICAL
CONNECTOR IS FULLY SEATED AS SHOWN BELOW . FAILURE TO DO THIS WILL
RESULT IN ABNORMAL PERFORMANCE OF THE VEHICLE.
INSTALLING A NISSAN ECU
NOTE: FOR SINGLE CONNECTOR TYPE ECU'S

The self-diagnostic system is useful to diagnose malfunctions in major sensors and actuators of the ECCS system. The ECU constantly monitors the function of these sensor and actuator circuits, regardless of ignition key position. If a malfunction occurs, information is stored in the ECU and can be retrieved from the memory by turning on the diagnostic mode selector, located on the side of the ECU. When activated the malfunction is indicated by flashing a red and green LED light emitting diode, also located on the ECU. Since all the self-diagnostic results are stored in the ECU memory, even intermittent malfunctions can be diagnosed.

A malfunctioning parts group is indicated by the number of both the red and green LEDs flashing. First, the red flashes, then the green flashes follow. The red LED refers to the number of the tens digit while the green one refers to the number of the units digit. For example, when the red LED flashes three times and then the green on flashes twice, this means the number 32. In this way, all problems are classified by the code numbers.

Perform self-diagnosis with engine sufficiently warmed up. After a malfunctioning component has been corrected, be sure to erase memory. To erase code memory:

Turn ignition switch ON.

Turn diagnosis mode selector ON.

Wait for 2 seconds.

Turn diagnosis mode selector OFF.

Wait 2 seconds. Memory erasure has been completed.

The stored memory would be lost if battery terminal is disconnected

See Figures 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11

Fig. 1: ECU code table-Z24i engine through 1986

Fig. 2: Diagnostic procedures-Z24i engine through 1986

Fig. 3: Diagnostic procedures-Z24i engine through 1986

Fig. 4: Diagnostic procedures-Z24i engine through 1986

Fig. 5: Diagnostic procedures-Z24i engine through 1986

Fig. 6: ECU code table-VG30i engine through 1986

Fig. 7: Diagnostic procedures-VG30i engine through 1986

Fig. 8: Diagnostic procedures-VG30i engine through 1986

Fig. 9: Diagnostic procedures-VG30i engine through 1986

Fig. 10: Diagnostic procedures-VG30i engine through 1986

Fig. 11: ECU code table-1987-88 Z24i and VG30i engines