GMC WORKSHOP

Malfunction indicator Lamp (MIL) (1994-1997)
Diagnostic Trouble Code Descriptions

Diagnostic Trouble Code Descriptions
MIL Code	Generic Scan Tool Code	HEX Code	DRB Scan Tool Display	Description of Diagnostic Trouble Code
	P0137 or P0138 or P0141	9C 7E 69	Downstream O2s Voltage Shorted to Ground Downstream O2 Sensor Shorted to Voltage Downstream O2 Heater Failure	Tested at cold start only after start to run. Downstream oxygen sensor input voltage maintained above the normal operating range. Downstream oxygen sensor heating element circuit malfunction. Tested at cold start only after start to run transfer.
22**	P0117 or P0118	1E 1F	ECT Sensor Voltage Too Low ECT Sensor Voltage Too High	Engine coolant temperature sensor input bolow minimum acceptable voltage. Engine coolant temperature sensor input above minimum acceptable voltage.
23**	P0112 or P0113	39 3A	Intake Air Temp Sensor Voltage Low Intake Air Temp Sensor Voltage High	Intake air temperature sensor input bolow the maximum acceptable voltage. Intake air temperature sensor input above the maximum acceptable voltage.
24**	P0121 or P0122 or P0123	84 1A 1B	TPS Voltage Does Not Agree With MAP Throttle Position Sensor Voltage Low Throttle Position Sensor Voltage High	TPS signal does not correlate to MAP sensor Throttle position sensor input bolow the minimum acceptable voltage Throttle position sensor input above the minimum acceptable voltage
25**	P0505 or P1294	19 8A	Idle Air Control Motor Circuits Target Idle Not Reached	A shorted or open condition detected in one or more of the idle air control motor circuits. Actual idle speed does not equal target idle speed.
27**	P0201	15	Injector #1 Control Circuit	Injector #1 output driver does not respond properly to the control signal.
	or P0202 or P0203 or P0204 or P0205 or	14 13 3D 45	Injector #2 Control Circuit Injector #3 Control Circuit Injector #4 Control Circuit Injector #5 Control Circuit	Injector #2 output driver does not respond properly to the control signal. Injector #3 output driver does not respond properly to the control signal. Injector #4 output driver does not respond properly to the control signal. Injector #5 output driver does not respond properly to the control signal.