HOW TO: Check Engine (A2) codes on an OBD1 car.
Posted: Sat Jun 13, 2009 4:13 pmHOW TO: Check Engine (A2) codes on an OBD1 car.
If you have a 850 from 93 to 95, or any ODB1 volvo, and the check engine light comes on, the first thing you do is go, "Oh Crap". No need to worry. You can check what is causing the CEL and clear the codes yourself. This is how.
1: Turn the key and put it in the on position (position 2).
2: Open the hood and locate the two small black boxes. The are located next to the windshield washer fluid fill.
3: Pull off the cover to the one on the left hand side. There is a small probe that is connected to the cover. Remove the probe and plug it into A2.
4: To find out what the code(s) is(are), press the black button next to the red LED for 1 full second. The LED will start to blink followed by a pause. For example: If the code was 2-3-4, the LED would go Blink Blink Pause Blink Blink Blink pause Blink Blink Blink Blink.
5: Repeat step 4 until you get all the codes. You will know that you have them all because the first one will repeat itself.
6: Once you have all of them, you can clear them by holding the black button down for 7 seconds. Wait a second and the LED will come on and not go out. When this happens, hold the black button down again for another 7 seconds. The LED will go out and the codes are cleared.
To check that all the codes are gone, press the black button again for 1 seconds. The LED should blink 1-1-1, which means no codes. Remove the probe from A2 and place it back in the cover. Replace the cover, turn to car off and then back on and the CEL will be off.
List of codes:
1-1-1: No faults detected
1-1-2: Fault in ECM
1-1-5: Injector 1
1-2-1: MAF sensor signal
1-2-3: ECT signal
1-2-5: Injector 2
1-3-1: RPM sensor signal missing
1-3-2: Battery voltage
1-3-5: Injector 3
1-4-3: Front knock sensor signal
1-4-4: Missing or Faulty Load Signal
1-4-5: Injector 4
1-5-3: Rear HO2S signal
1-5-4: EGR system leakage
1-5-5: Injector 5
2-1-2: Front HO2S signal
2-1-4: RPM sensor signal sporadic
2-2-3: IAC valve opening signal
2-2-5: A/C pressure sensor signal
2-3-1: Long term fuel trim, part load
2-3-2: Long term fuel trim, idling
2-3-3: Long term idle air trim
2-4-1: EGR system flow malfunction
2-4-5: IAC valve closing signal
3-1-1: VSS signal
3-1-4: CMP sensor signal
3-1-5: EVAP system
3-2-5: Memory failure
3-3-5: Request for MIL lighting from TCM
4-1-1: TP sensor signal
4-1-3: EGR temp sensor signal
4-1-4: Boost pressure regulation
4-1-6: Boost pressure reduction from TCM
4-3-2: Temperature warning level 1
4-3-3: Rear knock sensor signal
4-3-5: Front HO2S slow response
4-3-6: Rear HO2S compensation
4-4-3: Three way cat. Efficiency
4-4-4: Acceleration signal
4-5-1: Misfire cylinder 1
4-5-2: Misfire cylinder 2
4-5-3: Misfire cylinder 3
4-5-4: Misfire cylinder 4
4-5-5: Misfire cylinder 5
5-1-3: Temperature warning level 2
5-1-4: Engine cooling fan low speed signal
5-2-1: Front HO2S Preheating
5-2-2: Rear HO2S Preheating
5-3-1: Power stage group A
5-3-2: Power stage group B
5-3-3: Power stage group C
5-3-4: Power stage group D
5-3-5: TC control valve signal
5-4-1: EVAP valve signal
5-4-2: Misfire more than one cylinder
5-4-3: Misfire at least one cylinder
5-4-4: Misfire more than one cylinder, three way cat damage
5-4-5: Misfire at least one cylinder, three way cat damage
5-5-1: Misfire cylinder 1, three way cat damage
5-5-2: Misfire cylinder 2, three way cat damage
5-5-3: Misfire cylinder 3, three way cat damage
5-5-4: Misfire cylinder 4, three way cat damage
5-5-5: Misfire cylinder 5, three way cat damage
If you have a 850 from 93 to 95, or any ODB1 volvo, and the check engine light comes on, the first thing you do is go, "Oh Crap". No need to worry. You can check what is causing the CEL and clear the codes yourself. This is how.
1: Turn the key and put it in the on position (position 2).
2: Open the hood and locate the two small black boxes. The are located next to the windshield washer fluid fill.
3: Pull off the cover to the one on the left hand side. There is a small probe that is connected to the cover. Remove the probe and plug it into A2.
4: To find out what the code(s) is(are), press the black button next to the red LED for 1 full second. The LED will start to blink followed by a pause. For example: If the code was 2-3-4, the LED would go Blink Blink Pause Blink Blink Blink pause Blink Blink Blink Blink.
5: Repeat step 4 until you get all the codes. You will know that you have them all because the first one will repeat itself.
6: Once you have all of them, you can clear them by holding the black button down for 7 seconds. Wait a second and the LED will come on and not go out. When this happens, hold the black button down again for another 7 seconds. The LED will go out and the codes are cleared.
To check that all the codes are gone, press the black button again for 1 seconds. The LED should blink 1-1-1, which means no codes. Remove the probe from A2 and place it back in the cover. Replace the cover, turn to car off and then back on and the CEL will be off.
List of codes:
1-1-1: No faults detected
1-1-2: Fault in ECM
1-1-5: Injector 1
1-2-1: MAF sensor signal
1-2-3: ECT signal
1-2-5: Injector 2
1-3-1: RPM sensor signal missing
1-3-2: Battery voltage
1-3-5: Injector 3
1-4-3: Front knock sensor signal
1-4-4: Missing or Faulty Load Signal
1-4-5: Injector 4
1-5-3: Rear HO2S signal
1-5-4: EGR system leakage
1-5-5: Injector 5
2-1-2: Front HO2S signal
2-1-4: RPM sensor signal sporadic
2-2-3: IAC valve opening signal
2-2-5: A/C pressure sensor signal
2-3-1: Long term fuel trim, part load
2-3-2: Long term fuel trim, idling
2-3-3: Long term idle air trim
2-4-1: EGR system flow malfunction
2-4-5: IAC valve closing signal
3-1-1: VSS signal
3-1-4: CMP sensor signal
3-1-5: EVAP system
3-2-5: Memory failure
3-3-5: Request for MIL lighting from TCM
4-1-1: TP sensor signal
4-1-3: EGR temp sensor signal
4-1-4: Boost pressure regulation
4-1-6: Boost pressure reduction from TCM
4-3-2: Temperature warning level 1
4-3-3: Rear knock sensor signal
4-3-5: Front HO2S slow response
4-3-6: Rear HO2S compensation
4-4-3: Three way cat. Efficiency
4-4-4: Acceleration signal
4-5-1: Misfire cylinder 1
4-5-2: Misfire cylinder 2
4-5-3: Misfire cylinder 3
4-5-4: Misfire cylinder 4
4-5-5: Misfire cylinder 5
5-1-3: Temperature warning level 2
5-1-4: Engine cooling fan low speed signal
5-2-1: Front HO2S Preheating
5-2-2: Rear HO2S Preheating
5-3-1: Power stage group A
5-3-2: Power stage group B
5-3-3: Power stage group C
5-3-4: Power stage group D
5-3-5: TC control valve signal
5-4-1: EVAP valve signal
5-4-2: Misfire more than one cylinder
5-4-3: Misfire at least one cylinder
5-4-4: Misfire more than one cylinder, three way cat damage
5-4-5: Misfire at least one cylinder, three way cat damage
5-5-1: Misfire cylinder 1, three way cat damage
5-5-2: Misfire cylinder 2, three way cat damage
5-5-3: Misfire cylinder 3, three way cat damage
5-5-4: Misfire cylinder 4, three way cat damage
5-5-5: Misfire cylinder 5, three way cat damage