1995 Chevy S-10

  • 1995 CHEVROLET S-10

Computer problem
1995 Chevy S-10 4 cyl Two Wheel Drive Automatic 181000 miles

16 pin aldl obd1.5

To any body else that owns one of these

and any other 94-95 car or trck model with PCM OBD1.5 located under glovebox/kick panel, true OBD2
PCM's are located in engine compartment.
They also have a knock sensor mounted atop of it.
along with a MAF and a extra heated O2 sensor at
back of the CAT/Convt.
OBD1, OBD1.5 have a removeable PROM - OBD2 has
a EEPROM and is not removeable.

OBD1 was flashed with 160 baud/8192baud(J2234)
OBD1.5 with 160/8192 w/UART(J1849vpw)
OBD2 with 160/8198 w/UART-CAN H+/L-(J1850vpw)

OBD1 12 pin / A=Blk.W/Wht. Wire(ECM signal grd.)
B=Wht.W/Blk. Wire(160)
D=Wht. Wire (UART) ABS
E=Tan w/Blk. Wire (8192)
M=Orange wire (12vdc)
Jump A+B get code flashout, clear codes by unhooking Neg. Post on battery.

OBD1.5 16 pin / pin4=Chasiss Grd.(Blk. Wire)
pin5=PCM Signal Grd.(Blk.W/Wht. Wire
pin6=160/canh+(Wht.W/Blk. Wire)
pin9=8192 (Tan w/Blk. Wire)
pin12=UART(Wht. Wire)ABS
pin14=UART(pink wire)canL-
pin16=(12vdc)Orange wire
Jump 5+6 get code flashout, to clear out codes a scan
ner w/ OBD1/OBD2 protocals is needed with a GM
Specific (16 pin connector-Blue plug-in) or go to junk
yard and get a 12 pin ALDL and wire it like so.

( A to pin5, B to pin6, E to pin9, M to pin16)
Use the OBD1 connector on the 12 pin ALDL.

Do you
have the same problem?
Friday, September 25th, 2009 AT 7:07 PM

2 Replies


I have a 1995 Sonoma also 4cyl 2WD but stick and I seem to have a similar problem. But this post is the first I have ever heard of OBD1.5

I have an ODB2 data port under the dash on the driver side. I haven't climbed under it to look really close at the pins that are present/absent.

A couple of questions.

1) By "true OBD2 PCMs are located in the engine compartment, " are you saying that all unless you're directly connecting to the computer, your system is NOT an OBD2 design?

2) Can I take an ODB2 cable and hook it up to an OBD1 scanner to read ODB1 and OBD1.5 codes (whichever my truck has)? Or do I have to use the ALDL cable and a PC/laptop?


Was this
Thursday, October 22nd, 2009 AT 9:51 PM

Answer: 1 You have a 16 pin ALDL-if your pcm is inside the engine compartment, you should be OBD2
1996 EPA compliant. Any scanner with OBD2 protocals
w/a yellow 16pin ALDL plug should access computer.
If Computer is up under glovebox-you have a 1.5 OBD
it has a removeable PROM/MEM-CAL which can be re-
flashed(programmed) for performance.

Answer:2 YES to both, as long as you have the blue
16 pin ALDL GM Specific plug and your scanner has
OBD1/OBD2 protocals. (I use a AutoXray2500)
The yellow 16 pin ALDL plug is only for vechicles aft.
1995(1996 to present)

I hope this puts some light to this dark area

Was this
Friday, October 23rd, 2009 AT 8:20 PM

Please login or register to post a reply.

Recommended Guides