code 43,44
- Thread starter BrianJ
- Start date
midnightbluS10
Banned
Re: code 43,44
here's a list
http://forums.s-series.org/viewtopic.php?t=46418
here's a list
http://forums.s-series.org/viewtopic.php?t=46418
So your "check engine" or "service engine soon" light has come on. If you have a pre-1996**, you don't need an expensive scan-tool or code reader to check the codes, just a simple paper clip. Locate the ALDL (Assembly Line Diagnostic Lead). It is usually under the driver's side of the dash.
For most 1994 and back (OBD 1, 12 pin ALDL) short terminals A & B.
300){ this.height = Math.round(((screen.width-500)/this.width)*this.height); this.width = (screen.width-500); }" onclick="javascript:window.open('http://www.sethirdgen.org/images/aldl.jpg','','scrollbars=1,toolbar=0,resizable=1,menubar=0,directories=0,status=0')" alt="Posted Image, might have been reduced in size. Click Image to view fullscreen." title="Posted Image, might have been reduced in size. Click Image to view fullscreen." border="0" height="249" width="524">
In 1995 GM changed to OBD 1.5. Some late 1994 models are also OBD 1.5. For some of these, (OBD 1.5, 16 pin ALDL) you can obtain codes by shorting terminals 5 & 6.
300){ this.height = Math.round(((screen.width-500)/this.width)*this.height); this.width = (screen.width-500); }" onclick="javascript:window.open('http://www2.eboard.com/boards/9/50/68/tink/att-984326/aldl.jpg','','scrollbars=1,toolbar=0,resizable=1,menubar=0,directories=0,status=0')" alt="Posted Image, might have been reduced in size. Click Image to view fullscreen." title="Posted Image, might have been reduced in size. Click Image to view fullscreen." border="0">
Turn key on, but do not start engine. Find and Short terminals with a paper clip. The check engine light will begin to flash. The ECM (computer) will display a "code 12" by flashing the "service engine soon" light, indicating that the system is operating. A code 12 is simply one flash, followed by a brief pause, then two flashes in quick succession. This code will be flashed 3 times. If no other codes are stored, code 12 will flash until the diagnostic terminal ground is removed. After flashing code 12 3 times, the ECM will display any stored trouble codes. Each code will be flashed 3 times, then code 12 will be flashed again, indicating that the display of any stored trouble codes has been completed.
TROUBLE CODES:
Code Probable Cause
12 Diagnostic Mode
13 Oxygen sensor or circuit
14 Coolant sensor or circuit / high temperature indicated
15 Coolant sensor or circuit / low temperature indicated
16 Transmission speed error (4L60 or 4.3L "S" & "T" series w/ manual)
17 Crank signal circuit shorted or faulty ECM
18 Crank signal circuit open or faulty ECM
19 Fuel pump circuit short
19 Crankshaft position sensor (1988-1991 models)
20 Fuel pump circuit open
21 Throttle Position Sensor (TPS) circuit or plunger
22 Throttle Position Sensor (TPS) out of adjustment
21/22 Grounded wide-open-throttle (WOT) circuit at same time
23 Manifold Absolute Temperature (MAT) sensor or circuit / low temp.
24 Vehicle Speed Sensor (VSS) or circuit
25 Manifold Air Temperature (MAT) sensor or circuit / high temp.
26 Throttle switch circuit shorted
27 Throttle switch circuit open
31 Turbo over boost (Turbo models)
31 Canister purge solenoid circuit
31 Camshaft sensor or circuit
31 EGR circuit (1988 to 1990 TBI)
31 Shorted MAP sensor circuit
32 BARO sensor or circuit (carbureted models)
32 EGR circuit (fuel-injected models)
32 Open MAP sensor circuit
33 Manifold Absolute Pressure (MAP) sensor or circuit (low vacuum)
33 MAF (Mas Air Flow) sensor or circuit
33 Manifold Absolute Pressure (MAP) sensor signal voltage high
34 Manifold Absolute Pressure (MAP) sensor signal voltage low
34 MAF (Mas Air Flow) sensor or circuit
35 Idle Air Control (IAC) valve or circuit
35 Idle Speed Control (ISC) switch or circuit (shorted)
36 Mass Air Flow (MAF) sensor burn-off circuit
36 Closed throttle shift control (1991)
37 MAT sensor temp. high (1984-1986)
37 Brake switch stuck on (4L60-E transmission)
38 Brake Input Circuit (brake light switch)
38 MAT sensor temp. low (1984-1986)
38 Brake switch stuck off (4L60-E transmission)
39 Torque converter clutch
39 Knock sensor circuit shorted (4.3L, manual trans., "S" & "T" pick-up)
40 Power steering pressure switch circuit
41 No distributor signals to ECM, or faulty ignition module
41 Cylinder select error
42 Electronic Spark Timing (EST) circuit
43 Throttle Position Sensor (TPS) out of adjustment
43 Knock sensor signal
44 Oxygen sensor or circuit - lean exhaust
45 Oxygen sensor or circuit - rich exhaust
46 Power steering pressure switch (4 cylinder - air-conditioned modules)
46 Vehicle Anti-Theft System (VATS)
47 Air conditioning clutch and cruise circuit
48 Misfire diagnosis
53 System over-voltage (ECM over 17.7 volts)
53 EGR system (carbureted models)
53 Alternator voltage out of range
55 ECM/PCM error
55 Oxygen sensor circuit or ECM
56 Vacuum sensor circuit
58 PASS key fuel enable circuit
58 Transmission code - TTS high temp. (sensor or signal wire grounded)
59 Transmission code - TTS low temp. (sensor or signal wire open)
61 Oxygen sensor signal faulty
63 MAP sensor voltage high
64 MAP sensor voltage low
64 Right side oxygen sensor lean (dual sensor models)
65 Right side oxygen sensor rich (dual sensor models)
66 Air conditioning pressure sensor circuit
67 Air conditioning pressure sensor or clutch circuit (Chevrolet)
67 Cruise switch circuit
68 Air conditioning relay circuit (Chevrolet)
68 Cruise system problem
69 Air conditioning clutch circuit (Chevrolet)
69 Air conditioning head pressure switch circuit
69 Transmission code - Torque converter stuck on (4L60-E)
72 Gear selector switch (Chevrolet)
72 Transmission code - Vehicle Speed Sensor (VSS) signal loss (4L60-E)
75 System voltage low (charging system problem)
79 Transmission fluid temperature high (4L60-E)
81 Transmission code - QDM solenoid "A" (1st and 2nd gear) current error
82 Transmission code - QDM solenoid "B" (2nd and 3rd gear) current error
99 Power management, cruise control system
When the ECM sets a trouble code, the "check engine" or "service engine soon" light will come on and a trouble code will be stored in memory. If the problem is intermittent, the light will go out after 10 seconds, when the fault goes away. However, the trouble code will stay in the ECM memory until the battery voltage to the ECM is interrupted. Removing battery voltage for 10 seconds will clear all stored trouble codes. Trouble codes should always be cleared after repairs have been completed.
OBD-I codes can be very vague, and diagnosis sometimes isn't that simple. Most people think that a code 32 (EGR system) means the EGR valve is bad and needs replaced. This isn't always so!!! There are many components in the EGR system that could cause the code to set OTHER than the EGR valve itself!
