1993 Acura Legend DTC (Engine fault codes)

Tiny
JAMESEB
  • MEMBER
  • 1993 ACURA LEGEND
Computer problem
1993 Acura Legend 6 cyl Front Wheel Drive Automatic

Code do not display on computer. But I checked the old fashioned way, reroute. Got 5 long flashes.
What is code #?
Monday, August 23rd, 2010 AT 8:44 AM

3 Replies

Tiny
KHLOW2008
  • MECHANIC
  • 41,815 POSTS
Hi Jameseb,

Code 5 = MAP sensor, mechanical problem.

CODE 5: MAP SENSOR

1. Turn ignition off. Remove ACG (No. 15, 7.5-amp) from underdash fuse box for 10 seconds to reset ECM. Start engine. Connect jumper wire to self-diagnostic connector. Observe MIL. If light is off, problem is intermittent. Check all electrical connections and vacuum hoses. Test drive vehicle and retest.

2. If MIL is on and indicates Code 5, turn ignition off. Remove MAP hose at throttle body base. Connect a hand-held vacuum pump to MAP sensor, and apply vacuum. If vacuum does not hold, replace MAP sensor. If vacuum holds, connect vacuum hose and go to step 3.

3. Connect "T" fitting in vacuum hose between MAP sensor and throttle body base. See Fig. 6 . Start engine. If vacuum is not present, remove restriction from throttle body. If vacuum is present, turn ignition off. Connect ECM Test Harness (07LAJ-PT3010A ) between ECM and ECM connectors. See
Fig. 2 . Turn ignition on. Measure voltage between test terminals D17 (+) and D21 (-).

4. If voltage is not about 3 volts, replace MAP sensor. If voltage is about 3 volts, start engine and allow it to idle. Recheck voltage between terminals D17 and D21. If voltage is not about one volt at idle, replace MAP sensor. If voltage is about one volt, replace ECM and retest.


https://www.2carpros.com/forum/automotive_pictures/192750_ECMHArness93LegendFig02_1.jpg




https://www.2carpros.com/forum/automotive_pictures/192750_MAPSensor93LegendFig06_1.jpg



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Monday, August 23rd, 2010 AT 10:56 AM
Tiny
JAMESEB
  • MEMBER
  • 2 POSTS
Thanks for the information.I replaced the MAP sensor. Engine seems to be running ok.

I disconnected the battery and waited for about 10 minutes, to rid the computer memory of the codes. The check light came on instantly when I restarted the engine. Had been coming on well after engine ran for a while. When changing the Map sensor, I also replaced the engine coolant sensor. Have not checked for codes since reinstalled sensors.

Before replacing above, the codes were as follows:

5 slow (long0 flashes, pause, 3 short flashes, pause then 6 fast flashes.
Any idea as to all of these codes, I thought that the short flashes were for the Map sensor?
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Monday, August 23rd, 2010 AT 2:55 PM
Tiny
KHLOW2008
  • MECHANIC
  • 41,815 POSTS
Code 53 = Knock sensor
Code 6 = Coolant temperature sensor.

CODE 6: COOLANT SENSOR

1. Turn ignition off. Remove ACG fuse (No. 15, 7.5-amp) from underdash fuse box for 10 seconds to reset ECM. If light is off, problem is intermittent. Check for poor and loose connections at coolant sensor, ECM and right shock tower. Test drive vehicle and retest.

2. If MIL is on and indicates Code 6, operate engine until cooling fan comes on. Turn engine off. Disconnect connector from coolant sensor. Measure resistance between sensor terminals. If resistance is not 200-400 ohms, replace coolant sensor.

3. If resistance is 200-400 ohms, turn ignition on. Measure voltage between Red/White wire terminal (+) and body ground. If voltage is about 5 volts, go to step 5. If voltage is not about 5 volts, connect connector "D" of ECM Test Harness (07LAJ-PT3010A ) to ECM, leaving vehicle wiring harness disconnected. Turn ignition on. Measure voltage between test terminals D13 (+) and D22 (-). See
Fig. 2 .

4. If voltage is about 5 volts, repair open or short in Red/White wire between ECM terminal D13 and coolant sensor. If voltage is not about 5 volts, replace ECM and retest.

5. If voltage was about 5 volts in step 3, measure voltage between Red/White (+) and Green/White (-) wire terminals. If voltage is not about 5 volts, repair open in Green/White wire between ECM connector terminal D22 and coolant sensor. If about 5 volts are present, replace ECM and retest.

CODE 23 OR 53: KNOCK SENSOR
NOTE:
Repair any engine knocking sounds before performing test.

1. Turn ignition off. Remove ACG fuse (No. 15, 7.5-amp) from underdash fuse box for 10 seconds to reset ECM. Warm engine until cooling fan comes on. With transmission in Neutral, hold engine speed at 3000-4000 RPM for 10 seconds. Check for fault codes. If Code 23 or 53 is not present, problem is intermittent. Check for poor connections at ECM, knock sensor and wiring harness connectors. Test drive vehicle and retest.

2. If Code 23 or 53 is present, turn ignition off. Connect ECM Test Harness (07LAJ-PT3010A ) to ECM harness connectors, leaving ECM disconnected. See Fig. 2 .

3. Disconnect knock sensor connector. Check for continuity between test terminal D3 (right sensor) or D4 (left sensor) and body ground. If continuity is not present, go to step 4. If continuity is present, repair short in Red/Blue wire between ECM connector terminal D4 and left knock sensor or short in White wire between ECM connector terminal D3 and right
knock sensor. See Fig. 14 .

4. Check continuity between test terminal D4 and Red/Blue wire terminal at left knock sensor connector or between test terminal D3 and White wire terminal at right knock sensor connector. If continuity is not present, repair open in wire between ECM terminal D3 or D4 and knock sensor.

5. If continuity is present, reconnect knock sensors. Replace ECM with a known good unit. Warm engine until cooling fan comes on. With transmission in Neutral, hold engine speed at 3000-4000 RPM for 10 seconds. Check ECM for fault codes. If Code 23 or 53 is present, replace knock sensor. If Code 23 or 53 is not present, replace ECM.


https://www.2carpros.com/forum/automotive_pictures/192750_KnockSensor93LegemdFig14_1.jpg


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Tuesday, August 24th, 2010 AT 7:07 AM

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