NOTE: 96 & later are OBD2 systems and require a scanner. For an OBD2 code list, please see our Acura code list or the appropriate generic list.
Acura: Accessing Diagnostic Trouble Codes
86-94 Acura
- The Engine Control Unit (ECU) stores trouble codes. On the outside of the ECU case are one or two LEDs.
- If the ECU has 2 LEDs, ignore the Amber LED and look at the Red LED
- On 87-89 models, the ECU is located beneath the front passenger seat.
- 1990-1994 models locate the ECU under the dashboard on the passenger’s side beneath the carpet.
- Legend models provide a flip-out mirror that allows you to view the LEDs.
- Earlier models have a “window” at the base of the passenger front seat that allows you to view the LEDs.

Counting the Flashes
- To retrieve trouble codes, turn the ignition key to the “on” position with the engine off.
- 86-89 models: The ECU will flash many short blinks. The total number of blinks equals the code number. For example, 12 short blinks equals code 12, nine short blinks equals code 9, etc.. If more than one code is stored, the ECU will flash the codes in sequence (lowest to highest) with a pause between each code. The codes will repeat until the key is turned to the OFF position.
- 90-94 models: The ECU will flash a long blink to represent the first digit of the code, then a series of short blinks to represent the second digit. For example, 1 long blink, followed by 4 short blinks equals code 14. Four long blinks followed by five short blinks equals code 45.
- NOTE: Legend Models: If code 7 or 17 is stored and the S4 light on the transaxle indicator panel is also flashing, it may be necessary to diagnose the automatic transaxle control unit.
86–90 Legend & 86–91 Integra
- In the event of a PGM-FI system malfunction, the engine warning lamp will light and stay lit.
- When this condition occurs, it will be necessary to inspect the ECU LED display.
- On Integra models, the ECU contains a single red LED display.
- On Legend models, the ECU contains a red and a yellow LED display.
- The red LED should be used for both models when diagnosing PGM-FI system malfunctions.
- When the engine warning lamp is illuminated, proceed as follows:
- On all models except 1991 Integra, move front passenger seat to rear position.
- On 1991 Integra models, pull down passenger side carpet from under dashboard.
- On all models, turn ignition On and observe red LED on front or top of ECU. The LED will indicate diagnostic trouble codes (DTCs) by number of flashes.
NSX, Vigor, 91–95 Legend, 92–95 Integra & 91–96 NSX
In the event of a PGM-FI system malfunction, the Check Engine lamp will light and stay On. When this condition occurs, proceed as follows:
- Using a jumper wire, connect terminals of service check connector
- Service check connector location. 91–95 Legend & 91–96 NSXService check connector location. VigorService check connector location. 92–95 Integra
- The Check Engine lamp will indicate DTCs by the number of flashes.
96–01 Integra
When the Malfunction Indicator Lamp (MIL) has been on or if there is driveability problem, proceed as follows:
- To use OBD II scan tool, proceed as follows:
- To use MIL, proceed as follows:
97–01 NSX
When Malfunction Indicator Lamp (MIL) has been on or there is driveability
condition, proceed as follows:
- To use OBD II scan tool, proceed as follows:
- Connect scan tool to 16-pin data link connector (DLC) located under glove compartment under a removable cover.
- Turn ignition On.
- Follow scan tool manufacturer’s operating instructions to access DTCs.
- To use MIL, proceed as follows:
- Connect SCS service connector special tool No. 07PAZ-0010100, or equivalent, to service check connector located under passenger’s side of dash
- Turn ignition On.
- MIL will indicate DTC(s) by number of flashes.
2.2CL, 2.3CL, 2.5TL, 3.0CL, 3.2CL, 3.2TL 3.5MDX & 3.5RL
When Malfunction Indicator Lamp (MIL) has been on or there is driveability
problem, proceed as follows:
- To use OBD II scan tool, proceed as follows:
- Connect scan tool to 16-pin data link connector (DLC) located behind or under the ashtray on center console.
- Turn ignition On.
- Follow scan tool manufacturer’s operating instructions to access DTCs.
- To use MIL, proceed as follows:
- Connect SCS service connector special tool No. 07PAZ-0010100, or equivalent, to service check connector located under passenger’s side of dash.
- Turn ignition On.
- MIL will indicate DTC(s) by number of flashes.
- To use OBD II scan tool, proceed as follows:
SLX
Connect a suitable scan tool to the DLC (Data Link Connector), located at the lower LH of the instrument panel behind a small square cover.
Acura: Clearing Diagnostic Trouble Codes
Legend, Vigor, 86–95 Integra & 91–96 NSX
After making all necessary repairs, the DTCs should be cleared as follows from the ECU memory.- On 86–89 Integra models, remove hazard fuse at battery positive terminal for approximately 10 seconds to clear all stored DTCs.
- On 90 Integra models, remove hazard fuse in main fuse box for approximately 10 seconds to clear all stored DTCs.
- On 91–95 Integra models, remove back-up fuse from under hood fuse box for approximately 10 seconds to clear all stored DTCs.
- On 86–90 Legend models, remove alternator sense fuse in underhood relay box for 10 seconds to clear all DTCs.
- On 91–95 Legend models, remove No. 15 fuse from under dash fuse box for 10 seconds to clear all DTCs. This will also cancel power seat settings.
- On NSX models, remove clock fuse from main relay box, located in luggage compartment on RH side, for approximately 10 seconds to clear all DTCs. This will also cancel radio presets and clock setting.
- On Vigor models, remove back-up fuse from under hood fuse/relay box for approximately 10 seconds to clear all DTCs. This will also cancel radio presets and clock setting
2.2CL, 2.3CL, 2.5TL, 3.0CL, 3.2CL, 3.2TL, 3.5 MDX, 3.5 RL, 96–01 Integra & 97–01 NSX
- If using scan tool, follow scan tool instructions to clear ECM/PCM memory.
- If using MIL, turn ignition Off.
- On models except NSX and 99–01 3.2TL, remove Backup Radio Fuse from underhood fuse relay box for 10 seconds. On NSX models, remove Clock Fuse from underhood fuse relay box for 10 seconds. On all models, disconnect SCS service connector.
- On 99–01 3.2TL models, remove Clock Backup Fuse from passenger compartment under dash fuse relay box for 10 seconds. On all models, disconnect SCS service connector.
SLX
Follow scan tool instructions to clear PCM memory.
Acura: Diagnostic Trouble Codes 1986 – 2001
Vigor, Legend | |
2.2CL | |
2.3CL | |
2.5TL | |
3.0CL | |
3.2CL | |
3.5RL | |
SLX | |
86-94 | Acura Basic Codes |
88–95 | Integra |
91–96 | NSX |
96–01 | Integra |
96–98 | 3.2TL |
97–01 | NSX |
99–01 | 3.2TL & 3.5L MDX |
Acura: Diagnostic Trouble Codes 1991 – 2009
Model | Year | Engine identification | System |
---|---|---|---|
2.2CL | 1997 | F22B1 | Honda PGM-FI |
2.3CL | 1998-99 | F23A1 | Honda PGM-FI |
2.5TL | 1995-98 | G25A4 | Honda PGM-FI |
3.0CL | 1997-99 | J30A1 | Honda PGM-FI |
3.2CL | 2000-03 | J32A1/2 | Honda PGM-FI |
3.2TL | 1996-98 | C32A6 | Honda PGM-FI |
3.2TL | 1999-03 | J32A1 | Honda PGM-FI |
3.5RL | 1996-04 | C35A1 | Honda PGM-FI |
Integra 1.8L | 1996-01 | B18B1 | Honda PGM-FI |
Integra 1.8L VTEC | 1996-01 | B18C1/C5 | Honda PGM-FI |
MDX 3.5L | 2000-06 | J35A3/5 | Honda PGM-FI |
MDX 3.7L | 2007-09 | J37A1 | Honda PGM-FI |
NSX/NSX-T 3.0L | 1991-05 | C30A1 | Honda PGM-FI |
NSX/NSX-T 3.2L | 1997-05 | C32B1 | Honda PGM-FI |
RDX 2.3L | 2007-09 | K23A1 | Honda PGM-FI |
RL 3.5L | 2005-08 | J35A8 | Honda PGM-FI |
RL 3.7L | 2009 | J37A2 | Honda PGM-FI |
RSX 2.0L | 2002-06 | K20A2/3 | Honda PGM-FI |
SLX 3.2L | 1996-97 | 6VD1 | Isuzu MFI |
SLX 3.5L | 1998-99 | 6VE1 | Isuzu MFI |
TL 3.2L | 2004-08 | J32A3 | Honda PGM-FI |
TL 3.5L | 2007-08 | J35A8 | Honda PGM-FI |
TSX 2.4L | 2004-09 | K24A2 | Honda PGM-FI |
Why Does turning the key to the 2 before start the engine light flashes about 4 or 5 times then turn off, is that normal. Thanks in advance for any response and or comments
I have accura manufacturer in the year 2002.
But the Jeep is having fault .
When I checked it with engine it write DTCs with number 9 written with red colour .
What should I do?
i have a 2004 acura mdx that has a trouble code u0122
U0122 – Data bus: vehicle dynamics control module – no communication
https://www.troublecodes.net/ucodes/U0122/
1994 legend doesnt have a mirror for codes. What is the alternative?