wiring harness HELP
Thread Starter
Drifting
Joined: Jan 2005
Posts: 1,354
Likes: 325
From: San Antonio Tx
wiring harness HELP
I have a 86 Corvette and the factory service manual. The engine wiring harness I'm installing is from an 88. I'm 98% finished but I ran into a small problem with one connector under the dash that is different. The 86 has a white 6 wire connector with the following circuits: 419, 428, 437, 439, 461,and 959. The 88 harness has a 10 pin connector, only 6 are used but only 4 wires, circuits 428, 437,461 and 959 match the 86 connector. Anyone with an 88 wiring diagram that could help me out? On my diagram the connector is shown next to the ECM connector and says "to IP harness" I've been tracing wires with my ohm meter and I'm getting so confused! 
Thanks for any help you can give me.
Thanks for any help you can give me.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
That 10-pin connector is designated C-238 in the '88 Shop Manual and is wired as follows:
Pin....Wire Color.....Description
A......Dk Grn..........from HVAC control pin C3, AC compressor clutch ctrl
A......Dk Grn/Yel.....to blower control module pin C2, clutch on
B......Brn/Wht........from IC pin D12, VSS
B......Brn...............to ECM pin A10
C......N/C
D......Orn...............from IC pin D10, serial data out
D......Orn...............to ECM pin A8, serial data in
E......Wht..............from distributor EST pin C2
E......Wht..............to IC pin C5, tach in
F......N/C
G......Grn/Wht........from ECM pin A3
G......Grn/Wht........to C100 (and pin B of vapor canister purge sol)
H......N/C
J......Brn/Wht.........from ECM pin A5, SES light control
J......Brn/Wht.........to telltale assembly pin 3
K......N/C
Pinout on the 238 connector is:
-----^-----
| A........K |--
| B........J..| |
| C........H | |
| D........G | |
| E........F |---
-----------
Note: Due to drawing limitations of this Forum, I have shown one half of the connector from the wire end, not the plug end.
BTW, once I found six wires through the 238 connector I stopped looking as I have no was to locate all connections excpet by doint a page by page search for that connector number.
If your harness has any missing wires, please tell me the function so I can look up the info directly.
Pin....Wire Color.....Description
A......Dk Grn..........from HVAC control pin C3, AC compressor clutch ctrl
A......Dk Grn/Yel.....to blower control module pin C2, clutch on
B......Brn/Wht........from IC pin D12, VSS
B......Brn...............to ECM pin A10
C......N/C
D......Orn...............from IC pin D10, serial data out
D......Orn...............to ECM pin A8, serial data in
E......Wht..............from distributor EST pin C2
E......Wht..............to IC pin C5, tach in
F......N/C
G......Grn/Wht........from ECM pin A3
G......Grn/Wht........to C100 (and pin B of vapor canister purge sol)
H......N/C
J......Brn/Wht.........from ECM pin A5, SES light control
J......Brn/Wht.........to telltale assembly pin 3
K......N/C
Pinout on the 238 connector is:
-----^-----
| A........K |--
| B........J..| |
| C........H | |
| D........G | |
| E........F |---
-----------
Note: Due to drawing limitations of this Forum, I have shown one half of the connector from the wire end, not the plug end.
BTW, once I found six wires through the 238 connector I stopped looking as I have no was to locate all connections excpet by doint a page by page search for that connector number.
If your harness has any missing wires, please tell me the function so I can look up the info directly.
