OBDII info

[Tom Hussey]

Looking at my mail, I see that the subject wasn't described too well...
PIDs are just OBDII speak for parameter identification numbers. Each one
of those numbers represent some action or physical quantity. I have the
first 20 or so because they are published by SAE. In the table below I
mark the PID as "ROUTINE:" where the result is the call of some code on
a '97 Z28. Otherwise the PID returns the value of some location. That is
why OBDII code *should* be easier than earlier code to disassemble. If
you get the PIDs for you code you can know the function of 50-100
locations/routines without the pain involved in figuring stuff or the
expense of purchase of a second controller. Enjoy...

0000  SUPPORTED PID $01 - $20 BIT MAP FLASH CONST 
0001  ROUTINE: NUMBER OF EMISSION RELATED DTC
0003  ROUTINE: FUEL SYSTEM STATUS
0004  ROUTINE: CALCULATED LOAD
0005  ENGINE COOLANT TEMPERATURE
0006  LEFT SHORT TERM FUEL TRIM
0007  LEFT LONG TERM FUEL TRIM
0008  RIGHT SHORT TERM FUEL TRIM
0009  RIGHT LONG TERM FUEL TRIM
000B  MANAFOLD ABSOLUTE PRESSURE
000C  ENGINE RPM HIGH RES (RPM X 4)
000D  SPEED IN KPH
000E  ROUTINE: IGNITION TIMING ADVANCE
000F  INTAKE AIR TEMPERATURE -SCALED LINEAR LOCAL IAT
0010  MASS AIR FLOW
0011  THROTTLE POSITION SENSOR
0012  ROUTINE: COMMANDED SECOND AIR
0013  ROUTINE: REPORT O2 SENSOR CONFIGURATION
0014  ROUTINE: O2 B1S1
0015  ROUTINE: O2 B1S2
0018  ROUTINE: O2 B2S1
0019  ROUTINE: O2 B2S2
001C  ROUTINE: ?? RESERVED


BTW: This list is good for all cars with OBDII. The function of the PID
is the same.

-Tom






Tom Hussey wrote:
> 
> I wonder if anyone has access to info on GM specific OBDII PID codes.
> I
> am interested in as many as I can get my hands on as they all point at
> specific routines and locations within the ECM. I can share the
> locations when complete. In any case, here is a list of the supported
> PIDs. I expect one of these (or several) is used to flash the ECM.
> 
> 0000 0001 0003 0004 0005 0006 0007 0008
> 0009 000B 000C 000D 000E 000F 0010 0011
> 0012 0013 0014 0015 0018 0019 001C 0020
> 0022 0023 0024 0025 0026 0027 0028 0029
> 002B 002C 002D 0030 0031
> 
> 1104 1105 1106 1107 1108 1109 110A 110C
> 110D 110E 110F 1110 1111 1112 1113 1114
> 1115 1116 1140 1141 1142 1143 1144 1145
> 1146 1148 1149 1151 115E 116F 1170 1171
> 1176 1179 1190 1192 119D 119E 11A1 11A3
> 11BD 11C0 11C2 11C4 11D5 11D7 11D8 11DD
> 11DE 11E0 11E3 11E4 11E6 11E9 11EA 11EB
> 11EC 11ED 11F3 11F8 11F9 11FA 11FB
> 
> 1200 1201 1202 1203 1204 1205 1206 1207
> 1208 120A 120B 120C 1212 1216 1217 121A
> 121C 121D 1221 1226 1227 1228 122A 1232
> 1233 1234 1235 1236 1237 1238 1239 123A
> 123B 123C 123D 123F 1240 1241 1242 1243
> 1244 1245 1246 1247 1248 1249 124A 124B
> 124D 124E 1257 1258 1259 125A 125B 125D
> 125E 125F 1260 1261 1262 1263 1264 1265
> 1266 1267 1268 1269 126A 126B 126C 126D
> 126E 126F 1270 1271 1272 1273 1274 1275
> 1276 1277 1278 1279 127A 127C 127D 127E
> 127F 1280 1281 1282 1283 1284 1285 1286
> 1287 1288 1289 128A 128B 128C 128D 128E
> 12BE 12BF 12C0 12C1
> 
> 1601 1602
> 
> 1920 1921 1922 1923 1924 1925 1926 1927
> 1928 1929 192A 192B 192C 1941 1942 1970
> 1971 1972 1991 1992 1993 1994 1995 1996
> 1997 1998 1999 199B 199C 199D 199E 199F
> 19A0 19AD 19F3 19F4 19F5
> 
> 1A01
> 
> FC00 FC01 FC02 FC05 FC1F FC20 FC21 FC22
> FC23 FC24 FC25 FC26 FC27 FC28
> 
> -Tom