OBD I codes
 

OBD1 Codes Retrieval (Pre-1995 Cars and Trucks)


GM 1983-95 vehicles OBD1 codes self-retrieval


As the name implies, you can get the codes for GM cars or trucks yourself if the model of your vehicle is made before 1995, this means as soon as you see “check engine light” in your dash, you can get the code in minutes if you want.

Shown on the left is a picture of the connector where you get the GM OBD1 code.

When you find the adapter connector, use a jumper wire (see red wire above) and connect terminals A and B. Next turn your key on but don't start. Watch your check engine flash the code/s.

EXAMPLE: CODE 12: one long flash and two short flashesCODE 13: one long flash and 3 short flashes.

Note: code 12 is usually the first code you get and just ignore it.Watch the code after code 12, that's what you need.

GM common codes for OBD1 (for vehicles made before 1995)
12 System normal
13 oxygen sensor circuit open
14 coolant sensor high resistance or shorted
15 coolant sensor circuit low or open
16 direct ignition system (DIS) fault in circuit
17 cam position sensor fault
18 crank or cam sensor error
19 crank sensor circuit fault
21 tps sensor out of range
22 tps sensor signal voltage low
23 intake air temp sensor out of range, low
24 vehicle speed (vss) sensor circuit fault
25 air temp sensor sensor out of range, high
26 quad-driver module (computer) circuit #1 fault
27 quad-driver module (computer) 2nd gear circuit
28 quad-driver module (computer) circuit #2 fault
29 quad driver module (computer) 4th gear circuit
31 cam position sensor fault
32 egr circuit fault
33 map sensor signal out of range, high
34 map sensor signal out of range, low
35 idle air control sensor circuit fault
36 ignition system circuit error
38 brake input circuit fault
39 clutch input circuit fault
41 cam sensor circuit fault, igntion control circuit fault
42 electronic spark timing (EST) circuit grounded
43 knock sensor
or electronic spark control circuit fault
44 oxygen sensor lean exhaust
45 oxygen sensor rich exhaust
46 pass-key II circuit or ps.pressure switch circuit fault
47 pcm-bcm data circuit
48 misfire diagnosis
51 calibration error, mem-cal, ecm or eeprom failure
52 engine oil temperature circuit, low temperature indicated
53 battery voltage error or egr or pass-key II circuit
54 egr system failure or fuel pump circuit low voltage
55 a/d converter error or pcm not grounded or lean fuel or frounded reference voltage
56 quad-driver module #2 circuit
57 boost control problem
58 vehicle anti-theft system fuel enable circuit
61 a/c system performance or degraded oxygen sensor signal
62 engine oil temperature high temperature indicated
63 oxygen sensor right side circuit open or map sensor out of range
64 oxygen sensor right side lean exhaust indicated
65 oxygen sensor right side rich exhaust indicated
66 a/c pressure sensor circuit low pressure
67 a/c pressure sensor circuit or a/c clutch circuit failure
68 a/c compressor relay circuit failure
69 a/c clutch circuit head pressure high
70 a/c refrigerant pressure circuit high
71 a/c evaporator temperature sensor circuit low
72 gear selector switch circuit
73 a/c evaporator temperature circuit high
75 digital egr #1 solenoid error
76 digital egr #2 solenoid error
77 digital egr #3 solenoid error
79 vehicle speed sensor (vss) circuit signal high
80 vehicle speed sensor (vss) circuit signal low
81 brake input circuit fault
82 ignition control (IC) 3X signal error
85 prom error
86 analog/digital ecm error
87 eeprom error
99 power management


This information came from the following site:
http://www.extreme-check-engine-ligh...%20Decoder.htm

i found that site a while back but i have code 72 coming up for gear selector switch circuit. Where is that located on the truck I have 1994 Chevy k1500 silverado 1/2 ton pickup.

temperature gauge
 

need help my caprice1994 v8 i change water pump and coolant sensor
now my temperature gauge is very low near zero i change the temperature sender
with knew one but nothing change i grounded the wire from the gauge sender (found gauge is full hot

A little off topic, but is there a way to password protect the computer inside of the car? specifically i need to password protect a speed governor to prevent any tampering with it.

what is wrong?
 

In regards to 2009 Silverado:

I started the truck today since we have a couple potential buyers and the "Service Engine" light has
come on along with the "Stabilitrack" and "ABS" warnings.

You may research this yourself since you think everyone is lying to yourself, but I'll give you a run-
down of what I have found out:

This is a low-power mode that has nothing to do with the stabilitrack or the ABS, instead it
warns that there is a potential running problem. (remember how the Hyundai had the ESC
light come on because the taillights were out.)
My research shows this to be very common on this era of trucks from Chevy and most
common faults would be that the computer needs a re-flash or the throttle body needs replaced;
both of which would be covered under the powertrain warranty because they affect emissions

as well. It may also be simple that the gas is old and not producing the right O2 rating for the
computer; which is the most likely cause.

got this from ex who sent this any ideas what he is talking about?

Im looking for a code scanner for 94 caprice any suggestions?

Got 2 codes off my obd1
 

I got 2 codes from my obd1 by jumping it and they are 32 and 83 I have a new ETC new EGR valve but these codes are still on someone has told me that 83 could be 2-3 shift solenoid but I don't notice any problems from it can anyone help me???

I know this is quite a while ago, but the info in this code list is wrong. Code 72 for this truck is the vehicle speed sensor.

INNOVA 3123 can read Chevroletr OBD1 trouble code.