B18a1/auto swap. Tcu wiring. How to.

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Alright. I searched for this Info for a long damn time. Almost every hit on any search engine just takes you to an unanswered question about how to do it. On this site or another one. So I printed it up on Alldata and spent a bunch of time mapping it out. If you don't care, great. I've found at least 10 unanswered threads about this on this forum alone, so i know some people are wondering. Also the TCU is the same for obd0 and obd1 up to 94? or whenever they switched to the B18B1.

The Given ECU splice points are for OBD0 ONLY

TCU PIN CONNECTORS. LARGER CONNECTOR IS <A> SMALLER CONNECTOR IS <B>

Shape of A
XXXXXXXXXX 1 3 5 7 9 10 11 13 15 17
XXXX---XXXX 2 4 6 8 -- -- 12 14 16 18

Shape of B
XXXXXXX 1 3 5 7 8 9 11
XXX---XX 2 4 6 ---10 12

A1 A/C clutch relay SPLICE to ECU pin B3
A2 shift position reverse
A3 Tachometer Signal
A4 shift position park
A5 TW sensor SPLICE ECU pin C6
A6 shift position drive ATTACH TO WIRE REMOVED FROM ECU PIN B11
A7 Brake light SPLICE ECU pin C10
A8 shift position S
A9 S4 switch
A10 AT speed pulser. Match colors to grey wire on tranny
A11 ECU PIN B4
A12 shift position 2
A13 TPS sensor SPLICE to ECU PIN C7
A14 Speed Sensor. SPLICE TO ECU PIN B16
A15 PA Sensor SPLICE TO ECU PIN C9
A16 AT Speed pulser. Match color to Brn/Blk wire on tranny
A17 Shift LEver position indicator S4 Dimming circuit
A18 Shift interlock


B1 GROUND
B2 GROUND
B3 15 amp fuse for fast idle control solenoid
B4 15 amp fuse for fast idle control solenoid
B5 Lock up Control Solenoid. Match to green/black wire on tranny
B6 Lock up Control Solenoid. Match to red wire on tranny
B7 Shift Lever position indicator. Dimming/cancel circuit
B8 EMPTY
B9 Shift lever position indicator. Dimming/cancel circuit
B10 Shift control solenoid. Match to blue wire on tranny
B11 hazard light/backup fuse SPLICE TO ECU PIN B1
B12 Shift control solenoid. match to green wire on tranny

MOVE ECU PIN 10 to PIN 8. Tape up pin 8 wire. (previous autos only)
ECU PIN B4 is replaced with the wire from the TCU. Pin B4 was
Fan control relay. Im not sure if it was an input or an output. If it
Was an output signal, you will have to wire up a new way to turn your fans on
ECU PIN B11 is removed and soldered to TCU (explained above)

NOTE: IF YOU TRY TO COMPARE THIS TO ANOTHER DIAGRAM, THE PINS WILL NOT BE THE SAME. YOU MUST FOLLOW THE OBD1 STYLE ECU PINS AS I DREW THEM.

There ya go. Hope this helps the next person who wants to do this swap.
 
Haha no arguments here. 'Twas very confusing. I think there are a lot of wires that can be omitted without throwing a TCU CEL but i am still working on that.
 
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