How about little help ... with PCM connections on '97 & '98?

On 97 and 98 I need to see what gets connected to the PCM (EVERY wire). I'll compare that with mine ('99) for a PCM swap.

So, anybody knows a web site or something? For ex. in the FSM, what I need (for my '99), is in section 8W, but I don't want to buy the FSM's for 97 & 98 just for sections 8W.

Thanks.

PM me a reminder, and I'll break down the 1997 for you later - I've got a 1997 FSM.

I'm just on my way out to go to class right about now...

5-90

Just curious why your swapping the PCM from another year. Is your 99 PCM dead and you can't find a 99 PCM or is there some sort of performance gain from the 97-98 computer.

TIA.

HTH, YMMV, TANSTAAFL

1997 XJ PCM Connector Pinout.

C1 (Black Shell)

01 N/C
02 18 DKB/WHT Fused Ignition Switch Output (RUN/START)
03 N/C
04 18 BRN/YEL Sensor Return
05 18 BLK/WHT Park/Neutral Switch (*)
06 18 BLK/WHT Park/Neutral Switch (*)
06 18 BLK Ground (**)
07 18 GRY Ignition Coil Driver, #1 & #6
08 28 GRY/BLK Crankshaft Position Sensor Signal
09 N/C
10 18 YEL/BLK AIS Motor Close Signal
11 18 BRN/WHT AIS Motor Close Signal
12 18 BKB/BLK Power Steering Pressure Switch (***)
12 18 GRY Extended Idle Switch (Police Package) (****)
13 N/C
14 N/C
15 18 BLK/RED Intake/Charge Air Temperature Sensor
16 18 TAN/BLK Engine Coolant Temperature Sensor
17 18 ORG +5VDC Supply
18 18 TAN/YEL Camshaft Position Sensor Signal
19 18 GRY/RED AIS Motor Open Signal
20 18 VIO/BLK AIS Motor Close Signal (? The "Close" signals are duplicated above, may be a duplicated "Open" Signal)
21 N/C
22 16 DKG/BLK Fused B+
23 18 ORG/DKB Throttle Position Sensor
24 18 BLK/DKG Upstream HEGO Sensor
25 18 TAN/BLK Downstream HEGO Sensor
26 N/C
27 18 DKG/RED Manifold Absolute Pressure Sensor
28 N/C
29 N/C
30 N/C
31 14 BLK/TAN Ground
32 14 BLK/TAN Ground

C2 (White Shell)

01 N/C
02 N/C
03 N/C
04 18 WHT/DKB Injector Driver, #1
05 18 YEL/WHT Injector Driver, #3
06 18 PNK/BLK Injector Driver, #5 (*****)
07 N/C
08 N/C
09 N/C
10 18 DKG Alternator Field Driver
11 N/C
12 18 LTG/BLK Injector Driver, #6 (*****)
13 N/C
14 N/C
15 18 TAN Injector Driver, #2
16 18 LTB/BRN Injector Driver, #4
17 N/C
18 N/C
19 N/C
20 N/C
21 N/C
22 N/C
23 18 GRY/YEL Oil Pressure Sensor
24 N/C
25 N/C
26 N/C
27 18 WHT/ORG Vehicle Speed Sensor
28 N/C
29 N/C
30 N/C
31 18 VIO/ORG +5VDC Supply
32 N/C

C3 (Grey Shell) (RHD, M/T)

01 18 DKB/ORG A/C Compressor Clutch Relay Control
02 18 DKB/PNK Radiator Fan Relay Control
03 18 DKB/YEL Automatic Shutdown (ASD) Relay Control
04 18 TAN/RED Speed Control Vacuum Solenoid Control
05 18 LTG/RED Speed Control Vent Solenoid Control
06 N/C
07 N/C
08 N/C
09 N/C
10 N/C
11 18 YEL/RED Stop Switch Speed Control Source
12 18 DKG/ORG Automatic Shutdown (ASD) Relay Output
13 N/C
14 N/C
15 18 PNK/YEL Battery Temperature Sensor Signal
16 N/C
17 N/C
18 N/C
19 18 BRN Fuel Pump Relay Control
20 18 PNK/BLK Evapourator/Purge Solenoid Control
21 N/C
22 18 DKB/WHT A/C Switch Sense
23 18 LTG/RED A/C Select Signal
24 18 WHT/PNK Stop Lamp Switch Sense
25 18 DKG/ORG Alternator Source
26 18 DKB/RED Fuel Level Sense
27 18 PNK SCI Transmit
28 18 WHT/BLK CCS Bus -
29 18 LTG/BLK SCI Receive
30 18 VIO/BRN CCD Bud +
31 N/C
32 18 RED/LTG Speed Control Switch Sense

C3 (Grey Shell) (All Others)

01 18 DKB/ORG A/C COmpressor Clutch Relay Control
02 18 DKB/PNK Radiator Fan Relay Control
03 18 DKB/YEL Automatic Shutdown (ASD) Relay Control
04 18 TAN/RED Speed Control Vacuum Solenoid Control
05 18 LTG/RED Speed Control Vent Solenoid Control
06 N/C
07 N/C
08 N/C
09 N/C
10 N/C
11 18 YEL/RED Stop Switch Speed Control Source
12 18 DKG/ORG Automatic Shutdown (ASD) Relay Output
13 N/C
14 N/C
15 18 PNK/YEL Battery Temperature Sensor Signal
16 N/C
17 N/C
18 N/C
19 18 BRN Fuel Pump Relay Control
20 18 PNK/BLK Evapourator/Purge Solenoid Control
21 N/C
22 18 DKB/WHT A/C Switch Sense
23 18 LTG A/C Select Signal
24 18 WHT/PNK Stop Lamp Switch Sense
25 18 DKG/ORG Alternator Source
26 18 DKB/LTG Fuel LEvel Sense
27 18 PNK SCI Transmit
28 18 WHT/BLK CCD Bus -
29 18 LTG/BLK SCI Receive
30 18 VIO/BRN CCD Bus +
31 N/C
32 18 RED/LTG Speed Control Switch Sense

(*) With Automatic Transmission
(**) With Manual Transmission
(***) With 2.46L I4 Engine
(****) With 4.0L I6 Engine & Automatic Transmission
(*****) With 4.0L I6 Engine

DKB - Dark Blue
LTB - Light Blue
BRN - Brown
WHT - White
YEL - Yellow
RED - Red
VIO - Violet
BLK - Black
LTG - Light Green
DKG - Dark Green
TAN - Tan
ORG - Orange
PNK - Pink
GRY - Grey
N/C - No Connection

Where two colours are listed for a wire, the first colour indicates the "main" or "body" colour, and the second is the "tracer" or "stripe" colour.

Read each line as follows -

32 18 RED/LTG Speed Control Switch Sense, translates to:
"Cavity 32, 18 AWG Red wire w/Light Green Tracer, Speed Control SWitch Sense."

Since the illos in the FSM do not lend themselves well to determining orientation of the connector, you'll have to look for cavity/connector numbers in the module itself, or go by wiring colours, if they are available.


5-90

liviu said:

On 97 and 98 I need to see what gets connected to the PCM (EVERY wire). I'll compare that with mine ('99) for a PCM swap.

So, anybody knows a web site or something? For ex. in the FSM, what I need (for my '99), is in section 8W, but I don't want to buy the FSM's for 97 & 98 just for sections 8W.

Thanks.

Click to expand...

You can't just swap them out as things are different. A 98+ PCM will for example look for the LDP sensor which IIRC 97 didn't have and the 98 had depending on the area it was made for. There are other differences as well.

Thank you very much 5-90.

Kejtar: Thanks for your comment. That's why I am collecting the info, so I know what was diff. I can swap wires if I know the connections.

liviu said:

Kejtar: Thanks for your comment. That's why I am collecting the info, so I know what was diff. I can swap wires if I know the connections.

Click to expand...

You can't just swap the connection because you don't have the sensors on one and you do on the other.

You need to match your VIN and production date to get a proper PCM. This method will get you nowhere.

Kejtar said:

You can't just swap them out as things are different. A 98+ PCM will for example look for the LDP sensor which IIRC 97 didn't have and the 98 had depending on the area it was made for. There are other differences as well.

Click to expand...

The LDP system (only a matter of emission prefference) appears to be the only diff. Why would not a PCM that ignores the LDP work on a car that has an LDP system? The other way around I would understand...

THe sensor you are refering to is actually a contact (connector C14).

anony91xj said:

You need to match your VIN and production date to get a proper PCM. This method will get you nowhere.

Click to expand...

Why would I need to match the VIN, dates and PCM? The PCM doesn't care about the VIN and date, only the connections it has. If it gets the right signals on its inputs, it doesn't care.

JEEPZZ said:

Just curious why your swapping the PCM from another year. Is your 99 PCM dead and you can't find a 99 PCM or is there some sort of performance gain from the 97-98 computer.

TIA.

Click to expand...

I am planning on swapping the PCM and injectors. The idea is that in pre-99 the gain was with less concern to emissions and week design on parts (intake and exhaust). The 190HP was mostly coming from gas and (I speculate) timing curve.

I have custom exhaust and post-99 intake with 63/62mm TB. I am hoping the PCM would dump more gas and has a diff ignition curve while having parts with better design.

Kejtar said:

You can't just swap the connection because you don't have the sensors on one and you do on the other.

Click to expand...

i did the swap sometime ago (PCM and injectors). The engine runs a bit better actually. Hooked up the Apexi too and drove for a week. I guarantee you it works!!!