Wiring a B14 ECU to Run a B15 Car

This will enable all of the B15 Sentra and P11 G20 owners to use a JWT ecu even though JWT does not offer the programming for those cars.

What is needed:
1. B14 ECU, 95-97 se-r or 95-96 1.6L ecu ($100 TO $400)
2. B14 engine harness ($300)
3. JWT ecu retune ($500)

Just to give you an example of how extreme you can go, we used this service to install a GTi-R motor into a 2002 G20 with a JGY BB37R turbo kit, 72 lb injectors, Ford Cobra MAF, etc. If you are just adding 370cc injectors or 444cc injectors and a small turbo, it will certainly work for you.

This will still enable you to have cruise, A/C and all the normal operations. If you are using your existing motor and a JGY turbo kit, you will still your standard cold idle. If you are using another motor such as a bluebird, you will not have a traditional functioning AAC valve. The true beauty of this wiring job is that all the gauges in the dash and all the accessories still work since the harness inside the dash and under are not affected.

Procedure: Use the B15/P11 harness to control the motor, splice it into the B14 harness to connect to the B14 computer, and any wires we don't list, leave connected. If you are using a different motor, then you will need to do the traditional swapping of distributors, water sensors, and TPS, etc.

Another advantage of this is that if you want to put your car back to *stock*, all you have to do is resplice the B15/P11 harness back to factory....and you are done.

Here are the wires to change:
 This is by viewing from the Harness side of the B14 ECU.

Left number is B 14, right number is B15 harness.

Nothing = no wire in harness or at ECU

Make sure you solder and not “butt-splice”

Also, use quality electrical tape with a decent shield rating


B14 ECU PIN

B15 ECU PIN


1 to 35
2 is special, you will have to undo it from the harness and take it out to the B15 harness and put it in the extra hole in the 2 wire harness plug on the Dist. ***update, on some cars, this is not needed to be done, because the wire is there, so you connect 2 to pin 36 on the B15
3 to 32
4 to 31
5 nothing
6 nothing
7 nothing
8 to 21
9 to 48
10 to 48
11 nothing
12 nothing
13 nothing
14 to 13 and to 12
15 to 23
16 nothing
17 nothing
18 (MIL light…so don’t connect it :-) )
19 to 57 and to 48
20 to 41
21 to 44
22 to 42
23 to 92
24 nothing
25 to 46
26 to 86
27 nothing
28 nothing
29 nothing
30 nothing
31 nothing
32 nothing
33 nothing
34 nothing
35 nothing
36 nothing
37 nothing
38 to 43
39 to 108
40 to 75
41 to 85
42 nothing
43 to 58
44 to 75
45 to 85
46 to 62
47 to 61
48 to 73
49 to 111
50 to 58
51 to 70
52 to 63
53 to 65
54 to 81
55 nothing
56 to 110
57 nothing
58 nothing
59 nothing
60 nothing
61 to 112
62 to 72
63 to 64
64 nothing
65 nothing
66 nothing
67 nothing
68 nothing
69 nothing
70 to 67
(71 to 100 are not on the ECU)
101 to 6
102 to 101
103 (EGR, don’t connect)
104 to 105
105 nothing
106 to 108
107 to 103
108 to 3
109 to 107
110 nothing
111 to 106
112 to 106
113 to 67
114 nothing
115 to 4
116 nothing
117 nothing
118 to 108

Don’t forget that you may need have the EGR and other air sensors from your B15 harness and motor connected to the harness even though they are just dangling in the engine bay. We found this out when putting a VVL motor into a B15. It would not run for more than 15 minutes without having some of the EGR and Air sensors connected, even though the sensors were not measuring anything.

Pin 50 on the B15 says “Rear Window Defogger”, we skipped it