OBD 1.5 :( How do I obtain codes?
#1
12-12-2011, 09:49 PM
OBD 1.5 :( How do I obtain codes?
Hey guys, I tried searching and get conflicting reports. I verified it myself with the OBD1 sticker in the engine bay but I have a 16 pin port under the dash. My engine light is on and MPG is horrible. I want to get code but do not know how to. I have OBD2 scanners and they obv cannot help. Autozone says they cant do it either 
help!
help!
#3
12-13-2011, 07:32 PM
I've been wondering this also. I have a '95 with the ODB II connector. But my scan tool won't work with it. I know the paper clip trick for OBD I, but does this work for OBD "1.5"? Are there any other scanners that cost less than $300?
#4
12-13-2011, 10:13 PM
You can pull codes from an OBD 1.5 ecm with a paper clip. It's an OBD 1 ecm with OBD 2 ALDL connector. You just need to know which terminals to jumper. This is only valid for trucks with the ecm not under the hood.
IIRC, It's Pins 5 & 6
S-Series.Org • View topic - OBD1.5 & OBD2 people... please check this out...
edit:
DLC Connectors 
ACCESSING CODES
Although it is recommended that a diagnostic scan tool be used to read Diagnostic Trouble Code (DTC) (s), it may be possible to flash trouble codes on certain vehicles equipped with a "16" pin Data Link Connector (DLC) and a Powertrain Control Module (PCM) . The DLC connector terminal "6" (diagnostic terminal, if equipped) is the third terminal from the left of the DLC connector's top row. The terminal is grounded by connecting it to terminal "5" (internal PCM ground), the terminal to the left of terminal "6" on the top row of the DLC connector.
Once terminals "5" and "6" have been connected, the ignition switch must be moved to the "ON" position, with the engine not running. At this point, the MIL (Service Engine Soon) should flash Diagnostic Trouble Code (DTC) 12 three times consecutively. This would be the following flash sequence: "flash, pause, flash-flash, long pause, flash, pause, flash-flash, long pause, flash, pause, flash-flash." DTC 12 indicates that the diagnostic system is operating. If DTC 12 is not indicated, a problem is present within the diagnostic system itself, and should be referred to Diagnostic Charts . See: Testing and Inspection
Following the output of DTC 12, the MIL (Service Engine Soon) will indicate a diagnostic trouble code three times if a diagnostic trouble code is present, or it will continue to output DTC 12. If more than one diagnostic trouble code has been stored in memory, the diagnostic trouble codes will be output from the lowest to the highest, with each diagnostic trouble code being displayed three times.
ACCESSING CODES
Although it is recommended that a diagnostic scan tool be used to read Diagnostic Trouble Code (DTC) (s), it may be possible to flash trouble codes on certain vehicles equipped with a "16" pin Data Link Connector (DLC) and a Powertrain Control Module (PCM) . The DLC connector terminal "6" (diagnostic terminal, if equipped) is the third terminal from the left of the DLC connector's top row. The terminal is grounded by connecting it to terminal "5" (internal PCM ground), the terminal to the left of terminal "6" on the top row of the DLC connector.
Once terminals "5" and "6" have been connected, the ignition switch must be moved to the "ON" position, with the engine not running. At this point, the MIL (Service Engine Soon) should flash Diagnostic Trouble Code (DTC) 12 three times consecutively. This would be the following flash sequence: "flash, pause, flash-flash, long pause, flash, pause, flash-flash, long pause, flash, pause, flash-flash." DTC 12 indicates that the diagnostic system is operating. If DTC 12 is not indicated, a problem is present within the diagnostic system itself, and should be referred to Diagnostic Charts . See: Testing and Inspection
Following the output of DTC 12, the MIL (Service Engine Soon) will indicate a diagnostic trouble code three times if a diagnostic trouble code is present, or it will continue to output DTC 12. If more than one diagnostic trouble code has been stored in memory, the diagnostic trouble codes will be output from the lowest to the highest, with each diagnostic trouble code being displayed three times.
Last edited by midnightbluS10; 12-13-2011 at 10:19 PM.
#6
10-03-2012, 09:30 PM
code scanner
If you have a diagnostic port under the dash, you have a obd 1,5 system. Most code readers won't talk to the computer. The Autoxray code scout with the GM specific cable (ordered seperately) will connect and read and clear codes.
If you can get the codes, I have a factory service manual for the 95 year covering the PCM and the VCM systems.
You came for answers and I may have a few. Don't hesitate to ask.
If you can get the codes, I have a factory service manual for the 95 year covering the PCM and the VCM systems.
You came for answers and I may have a few. Don't hesitate to ask.
#7
01-16-2021, 11:30 AM
So my 95 having the computers on the passenger fender and the OBDII connector under the dash is the 1.5 and I check those codes by connecting pins 5 and 6 on the top row and switching the key on and ounting the flashing as stated above? I hope this works 8)
