I have listed a bunch of ECM/PCM fault code below (1991 "L", 1988 "C" and 1988 "3").
PCM codes (for 1991 PCM ("L") Toronado)
|
Code |
Description |
|
12 |
No fault |
|
13 |
O2 sensor (open circuit) |
|
14 |
Coolant temperature (too high => low resistance), 85C - 95C -> 1.5 to 2volts, 300 - 200 ohms. 0C -> 9500 ohms. |
|
15 |
Coolant temperature (too low => high resistance, over 53000 ohms (approx.)) |
|
16 |
System voltage too high/low (<9, >17v) |
|
17 |
Spark reference circuit |
|
21 |
Throttle position sensor, voltage too high (>4.8v) |
|
22 |
Throttle position sensor, voltage too low (<0.2v) |
|
23 |
Intake air temperature, too low (high resistance) |
|
24 |
Vehicle speed sensor |
|
25 |
Intake air temperature, too high (low resistance) |
|
26 |
Quad driver fault (the quad drivers output various PCM/ECM signals) |
|
31 |
PRNDL switch (wrong parity or selection does not match speed) |
|
34 |
Mass airflow sensor (too low) (no signal possibly) |
|
36 |
Transaxle shift problem |
|
38 |
Brake input circuit (several deccelerations (20) from over 35mph to 0 without brake pedal input detected) |
|
41 |
Cam sensor circuit (no signal possibly). A lost cam sensor magnet is a common cause. A scope on circuit 630 (black), should show 5v for 85%, 0v for 15% of the time, at half engine speed. The ignition module does not process this signal, it is passed straight through. Car should restart with this code, with a 1 in 6 chance of sequencing the injectors correctly. |
|
42 |
Electronic spark timing (open or grounded signal possibly) |
|
43 |
Electronic spark control (knock circuit) (open or grounded signal possibly) |
|
44 |
O2 sensor (lean) |
|
45 |
O2 sensor (rich) |
|
51 |
Mem-cal error (the mem cal is the PROM that controls the PCM/ECM function and is either the wrong one or incorrectly fitted) |
|
58 |
Personal Automotive Security System (Pass-key) fuel enable circuit (lost signal) |
|
61 |
Cruise vent solenoid (improper responses) |
|
62 |
Cruise vac solenoid (improper responses) |
|
65 |
Cruise servo position circuit (improper signal, open or ground) |
|
67 |
Cruise switches circuit (implausible switch behaviour) |
|
68 |
Cruise system problem (cruise actual position sensor too far different from commanded position) |
And for the 1988 ECM ("C") Delta 88
|
Code |
Description |
|
12 |
No fault |
|
13 |
O2 sensor (open circuit) |
|
14 |
Coolant temperature (too high => low resistance), 85C - 95C -> 1.5 to 2volts, 300 - 200 ohms. 0C -> 9500 ohms. |
|
15
|
Coolant temperature (too low => high resistance, over 53000 ohms (approx.)) |
|
16 |
System Voltage too high |
|
21 |
Throttle position sensor, voltage too high (>4.8v) |
|
22 |
Throttle position sensor, voltage too low (<0.2v) |
|
23 |
Manifold air temperature, too low (high resistance) |
|
24 |
Vehicle speed sensor |
|
25 |
Intake air temperature, too high (low resistance) |
|
26
|
Quad driver fault (quad drivers are the power transistors on the output stage of the ECM) |
|
27, 28, 29
|
Gear switch problems. There are three pressure switches in the tranny normally closed, they report current (actual) gear to the ECM. 27 is 2nd, 28 is 3rd, 29 is 4th. At start all should be closed. When the ECM determines from rpm and engine speed that it must be in 4th, if any of these switches are closed the appropriate code will be set. |
|
31 |
Park/Neutral circuit, similar to codes 27-29 but not a pressure switch |
|
34 |
Mass Air Flow sensor (too low) (no signal possibly) |
|
38
|
Brake Input circuit (several deccelerations (20) from over 35mph to 0 without brake pedal input detected) |
|
39
|
Torque Convertor lockup circuit (TCC) |
|
41 |
Cam sensor circuit (no signal possibly). A lost cam sensor magnet is a common cause. A scope on circuit 630 (black), should show 5v for 85%, 0v for 15% of the time, at half engine speed. The ignition module does not process this signal, it is passed straight through. Car should restart with this code, with a 1 in 6 chance of sequencing the injectors correctly. |
|
42 |
Electronic spark timing (open or grounded signal possibly) |
|
43 |
Electronic spark control (knock circuit) (open or grounded signal possibly) |
|
44 |
O2 sensor (lean) |
|
45 |
O2 sensor (rich) |
|
48
|
Misfire diagnosis (could be caused by faulty O2 sensor, fix O2 sensor first) |
|
51 |
Mem-cal error (the mem cal is the PROM that controls the PCM/ECM function and is either the wrong one or incorrectly fitted) |
|
63, 64, 65 |
EGR valve fault, ECM suspects one (or more, each code is a different valve) of the three valves is leaking exhaust gas when it should be shut off? (Set after a long coast downhill?) |
And for the 1988 ECM ("3") Delta 88 (might be OK for "B" motor too, not sure of this though.)
|
Code |
Description |
|
12 |
No fault |
|
13 |
O2 sensor (open circuit) |
|
14 |
Coolant temperature (too high => low resistance), 85C - 95C -> 1.5 to 2volts, 300 - 200 ohms. 0C -> 9500 ohms. |
|
15 |
Coolant temperature (too low => high resistance, over 53000 ohms (approx.)) |
|
21 |
Throttle position sensor, voltage too high (>4.8v) |
|
22 |
Throttle position sensor, voltage too low (<0.2v) |
|
23 |
Manifold air temperature, too low (high resistance) |
|
24 |
Vehicle speed sensor |
|
25 |
Intake air temperature, too high (low resistance) |
|
32 |
Exhaust Gas Recirculation circuit |
|
33 |
Mass Air Flow sensor (too high) |
|
34 |
Mass Air Flow sensor (too low) (no signal possibly) |
|
41 |
Cam sensor circuit (no signal possibly). A lost magnet will result in a no start condition. |
|
42 |
Electronic spark timing (open or grounded signal possibly) |
|
43 |
Electronic spark control (knock circuit) (open or grounded signal possibly) |
|
44 |
O2 sensor (lean) |
|
45 |
O2 sensor (rich) |
|
51 |
Mem-cal error (the mem cal is the PROM that controls the PCM/ECM function and is either the wrong one or incorrectly fitted) |
|
52 |
Cal-pac error |
|
55 |
ECM error |