Car still won't start? Here is my untested theory on how to bypass the immobilizer "kill" function.
UNTESTED THEORY: I have NOT tested this and your car may catch fire, blow up, fry itself, and/or generally be unhappy. I suspect however, it will work and am happy for your feedback, so we can finally have a workable solution for a car that is 20+ years old and often sub-$5K. I’m not worried this solution would lead to stolen cars because it will take a long time to access all these parts and for whatever reason, thieves who know of a quicker way (sub 5 minutes) have not posted how they are doing it – that would be nice to know by the way!
Theory: The lack of a valid RFID signal from key results in an 86S fault (i.e., no power is supplied to 86S, fault code 25), which is why a suggested fix is to check fuse E1 (fifth row down from the top - first fuse on the left (7.5A)). Bridging 30 and 86S at the ignition switch stage provides power to 86S, which is pin 16 [Terminal 15] on the immobilizer. You also need power on pin 36 at the immobilizer, which I believe happens if you have a valid RFID. Thus, you will need to bridge 16 and 36 on the immobilizer. I’m not sure what the ECU does with the signal from the immobilizer but you can force your ECU to power up by bridging it at the relay and best to bridge the start lock relay as well. Your car “should” start now.
STEP 1: IGNITION SWITCH
Bridge wires/pins 30 and 86 S [when I say bridge, I mean keep the wires connected to the switch but splice in some wire that will connect 30 and 86S so that 30 will power 86S)
STEP 2: IMMOBIZLIER
Bridge wires/pins 16 - Terminal 86 S [Orange Wire] and 36 - Terminal 15 [Black/Brown Wire]
STEP 3: DME/ECU RELAY IN REAR TRUNK
Pull out relay and bridge wires/pins 30, 87 and 87B
Do NOT leave this in place, as the fuel pump will continue to run and the DME will continue to draw power.
STEP 4: START LOCK RELAY IN REAR TRUNK
Pull out relay and bridge wires/pins 30 and 87
STEP 5: OPTIONAL: CLUTCH SAFETY SWITCH (not needed but easier to test if you don’t need to push in clutch all the time; and switch often fails and car won’t start]
Pull both connectors out of switch and connect the wires to each other so your car will now start without the need of pushing in the clutch.
986 IMMOBOLIZER PINS MAP
(see attached image below)
Plug I [Blue connector]
Terminal: - Antenna
3 - Immobilizer data
4 - Immobilizer control
5 - Driver's door secured
6 - Convertible top closed
7 - Driver's door closed
8 - Passenger compartment monitoring on
9 - Convertible top compartment lid
10 - Central locking button open
11 - External input 1
13 - Luggage compartment lid, rear
14 - External input 2
15 - Deactivation
16 - Terminal 86 S (buzzer contact) [Orange Wire]
17 - Luggage compartment light, rear
18 - Power window control
22 - Antenna (shield)
24 - Passenger compartment monitoring, signal input
25 - Driver's door closed
26 - Oddments tray
27 - Radio contact
28 - Passenger's door secured
29 - Central locking button closed
30 - Driver's door locked
31 - Luggage compartment lid, front
32 - Passenger's door locked
33 - Input, crash sensor
34 - Release, luggage compartment lid, rear
35 - Priming
36 - Terminal 15 [Black/Brown Wire]
37 - Luggage compartment light, front
39 - Alarm readiness light
40 - Comfort, opening
41 - Indicator, door locked
42 - Comfort, closing
Plug II
Terminal:
1 - Terminal 31
2 - Positive, alarm horn
3 - Servo motor, central locking system
4 - Load disconnection
5 - Actuator, tank cap
6 - Direction indicator light, left
7 - Terminal 30 input
8 - Terminal 30 output
9 - Servo motor, central locking system 10 - Actuator, tank cap
11- Interior light
12 - Direction indicator light, right