why does my SES light comes on?
Thread Starter
Racer
Joined: Oct 2005
Posts: 405
Likes: 0
From: 1984 crossfire, Alhaurin de la Torre Malaga, Spain
why does my SES light comes on?
It is a 91. Runs fine. But, when doing the highway for approx 30 -60 minutes, the SES light comes on. No overheating, everything seems ok. When I stop the engine and start again, the SES is off. When continuing the highway, after 20 - 40 minutes the SES comes on again.
There are no codes stored.
How can I find the reason? heeeeelp
There are no codes stored.
How can I find the reason? heeeeelp
Racer
Joined: Mar 2010
Posts: 291
Likes: 1
From: Temecula Cali
It is a 91. Runs fine. But, when doing the highway for approx 30 -60 minutes, the SES light comes on. No overheating, everything seems ok. When I stop the engine and start again, the SES is off. When continuing the highway, after 20 - 40 minutes the SES comes on again.
There are no codes stored.
How can I find the reason? heeeeelp
There are no codes stored.
How can I find the reason? heeeeelp
thats all i can think of....
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Burning Brakes
Joined: May 2007
Posts: 965
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From: turn 12 at Road America or TX
Safety Car
Joined: Jan 2008
Posts: 3,939
Likes: 1
From: Vero Beach Florida
You can also use a paper clip to read the codes
1985-1991: ECM Codes
Code #12: Normal No Codes.
Code #13: Open Oxygen Sensor Circuit.
Code #14: Coolant Sensor Circuit Low.
Code #15: Coolant Sensor Circuit High.
Code #21: Throttle Position Sensor High.
Code #22: Throttle Position Sensor Low.
Code #23: Manifold Air Temperature Circuit High.
Code #24: Vehicle Speed Sensor.
Code #25: Manifold Air Temperature Circuit Low.
Code #32: EGR System Failure.
Code #33: Mass Air Flow Sensor High.
Code #34: Mass Air Flow Sensor Low.
Code #36: Mass Air Flow Sensor Burn-Off Function Fault.
Code #41: Cylinder Select Error.
Code #42: Electronic Spark Timing.
Code #43: Electronic Spark Control.
Code #44: Lean Exhaust indication.
Code #45: Rich Exhaust Indication.
Code #46: Vehicle Anti Theft Fault.
Code #51: Faulty Mem-Cal.
Code #52: Fuel Calpak Missing.
Code #52: (1990-91 Corvette Only): Engine Oil Temperature Sensor Low.
Code #53: System Over Voltage.
Code #54: Fuel Pump Circuit Low Voltage.
Code #55: Defective ECM.
Code #62: Engine Oil Temperature Sensor Circuit High.
1985-1991: ECM Codes
Code #12: Normal No Codes.
Code #13: Open Oxygen Sensor Circuit.
Code #14: Coolant Sensor Circuit Low.
Code #15: Coolant Sensor Circuit High.
Code #21: Throttle Position Sensor High.
Code #22: Throttle Position Sensor Low.
Code #23: Manifold Air Temperature Circuit High.
Code #24: Vehicle Speed Sensor.
Code #25: Manifold Air Temperature Circuit Low.
Code #32: EGR System Failure.
Code #33: Mass Air Flow Sensor High.
Code #34: Mass Air Flow Sensor Low.
Code #36: Mass Air Flow Sensor Burn-Off Function Fault.
Code #41: Cylinder Select Error.
Code #42: Electronic Spark Timing.
Code #43: Electronic Spark Control.
Code #44: Lean Exhaust indication.
Code #45: Rich Exhaust Indication.
Code #46: Vehicle Anti Theft Fault.
Code #51: Faulty Mem-Cal.
Code #52: Fuel Calpak Missing.
Code #52: (1990-91 Corvette Only): Engine Oil Temperature Sensor Low.
Code #53: System Over Voltage.
Code #54: Fuel Pump Circuit Low Voltage.
Code #55: Defective ECM.
Code #62: Engine Oil Temperature Sensor Circuit High.
Thread Starter
Racer
Joined: Oct 2005
Posts: 405
Likes: 0
From: 1984 crossfire, Alhaurin de la Torre Malaga, Spain
Thread Starter
Racer
Joined: Oct 2005
Posts: 405
Likes: 0
From: 1984 crossfire, Alhaurin de la Torre Malaga, Spain
Thread Starter
Racer
Joined: Oct 2005
Posts: 405
Likes: 0
From: 1984 crossfire, Alhaurin de la Torre Malaga, Spain
You can also use a paper clip to read the codes
1985-1991: ECM Codes
Code #12: Normal No Codes.
Code #13: Open Oxygen Sensor Circuit.
Code #14: Coolant Sensor Circuit Low.
Code #15: Coolant Sensor Circuit High.
Code #21: Throttle Position Sensor High.
Code #22: Throttle Position Sensor Low.
Code #23: Manifold Air Temperature Circuit High.
Code #24: Vehicle Speed Sensor.
Code #25: Manifold Air Temperature Circuit Low.
Code #32: EGR System Failure.
Code #33: Mass Air Flow Sensor High.
Code #34: Mass Air Flow Sensor Low.
Code #36: Mass Air Flow Sensor Burn-Off Function Fault.
Code #41: Cylinder Select Error.
Code #42: Electronic Spark Timing.
Code #43: Electronic Spark Control.
Code #44: Lean Exhaust indication.
Code #45: Rich Exhaust Indication.
Code #46: Vehicle Anti Theft Fault.
Code #51: Faulty Mem-Cal.
Code #52: Fuel Calpak Missing.
Code #52: (1990-91 Corvette Only): Engine Oil Temperature Sensor Low.
Code #53: System Over Voltage.
Code #54: Fuel Pump Circuit Low Voltage.
Code #55: Defective ECM.
Code #62: Engine Oil Temperature Sensor Circuit High.
1985-1991: ECM Codes
Code #12: Normal No Codes.
Code #13: Open Oxygen Sensor Circuit.
Code #14: Coolant Sensor Circuit Low.
Code #15: Coolant Sensor Circuit High.
Code #21: Throttle Position Sensor High.
Code #22: Throttle Position Sensor Low.
Code #23: Manifold Air Temperature Circuit High.
Code #24: Vehicle Speed Sensor.
Code #25: Manifold Air Temperature Circuit Low.
Code #32: EGR System Failure.
Code #33: Mass Air Flow Sensor High.
Code #34: Mass Air Flow Sensor Low.
Code #36: Mass Air Flow Sensor Burn-Off Function Fault.
Code #41: Cylinder Select Error.
Code #42: Electronic Spark Timing.
Code #43: Electronic Spark Control.
Code #44: Lean Exhaust indication.
Code #45: Rich Exhaust Indication.
Code #46: Vehicle Anti Theft Fault.
Code #51: Faulty Mem-Cal.
Code #52: Fuel Calpak Missing.
Code #52: (1990-91 Corvette Only): Engine Oil Temperature Sensor Low.
Code #53: System Over Voltage.
Code #54: Fuel Pump Circuit Low Voltage.
Code #55: Defective ECM.
Code #62: Engine Oil Temperature Sensor Circuit High.
Regards.
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Thread Starter
Racer
Joined: Oct 2005
Posts: 405
Likes: 0
From: 1984 crossfire, Alhaurin de la Torre Malaga, Spain
Thread Starter
Racer
Joined: Oct 2005
Posts: 405
Likes: 0
From: 1984 crossfire, Alhaurin de la Torre Malaga, Spain
Vader
I have EGR, but there is no temp sensor. I did look, but I couldn't find a plugged hole either at the place where the sensor is mounted in the photo in the thread. There is als very little space to put it. And no loose wire that has been connected.
Can it be that there are versions with EGR but without sensor?
I made photo's but can't find a way to include them into this answer.
I have EGR, but there is no temp sensor. I did look, but I couldn't find a plugged hole either at the place where the sensor is mounted in the photo in the thread. There is als very little space to put it. And no loose wire that has been connected.
Can it be that there are versions with EGR but without sensor?
I made photo's but can't find a way to include them into this answer.
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
There is no EGR function without the sensor/solenoid. Either its there or someone removed it.
http://members.shaw.ca/corvette86/EGR%20System.pdf diagram C7-5
You can create a photobucket account and upload the pics there or some webservice.
http://members.shaw.ca/corvette86/EGR%20System.pdf diagram C7-5
You can create a photobucket account and upload the pics there or some webservice.
Pro
Joined: May 2006
Posts: 637
Likes: 0
It all depends were/how you look...
On a 1991, there is no sensor, the function is incorporated in the ECM.
There is a EGR solenoid otoh, it 's located right under the TB/plenum in the front.
The 86 doesn't have that one.
Where the 86 has a temp sensor on top of the isolated tube at the rear of the engine, the tube on the 91 continues right down to the cat/exhaust.
My 2 bux
On a 1991, there is no sensor, the function is incorporated in the ECM.
There is a EGR solenoid otoh, it 's located right under the TB/plenum in the front.
The 86 doesn't have that one.
Where the 86 has a temp sensor on top of the isolated tube at the rear of the engine, the tube on the 91 continues right down to the cat/exhaust.
My 2 bux
