SES Code H41 I'm new and clueless please help.
Thread Starter
Intermediate
Joined: May 2008
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From: Greenwood,,,,Ar 1991 Coupe
SES Code H41 I'm new and clueless please help.
I have a 91 coupe, I've had it for about a month now, and most of the time it runs great. However sometimes the SES light comes on and then the thing runs at about half the power, the a/c stops running the speedometer goes to zero and SYS start flashing beside where the speedometer should be. I checked the codes with a paperclip and got
H41 and H33. I have done a search and was able to get some info leading me in the direction of a ECM going out, but thought I would post this to see what the rest of you guy's could tell me, Thanks in advance for any help you give me.
H41 and H33. I have done a search and was able to get some info leading me in the direction of a ECM going out, but thought I would post this to see what the rest of you guy's could tell me, Thanks in advance for any help you give me.
Safety Car
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From: :45 minutes from everywhere / E-I-E-I-O
I can't get my '94 to light up H41 again, like it did when I took a short trip last week. It will probably wait till I'm on the road again.
I got about 11 pages of FSM/AllDATA for H41, but again, mine's a '94. If it's good for a '91 too, I'll get 'em scanned and posted up.
See what you can find out on '91 vs '94...
I got about 11 pages of FSM/AllDATA for H41, but again, mine's a '94. If it's good for a '91 too, I'll get 'em scanned and posted up.
See what you can find out on '91 vs '94...
Pro
Joined: May 2006
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If it´s ECM codes you´re talking about then 33 stands for manifold absolute pressure (MAP) sensor circuit (signal voltage high-low vacuum).
Code 41 stands for cylinder select error (faulty or incorrect MEM-CAL)
Both cases were H (history) for you. I would clear the codes by unhooking the neg. batt. cable for a minute or so and put back on and go for a drive and see if the codes come back.
Is engine idle ok, steady at 650 or 700?
Code 41 stands for cylinder select error (faulty or incorrect MEM-CAL)
Both cases were H (history) for you. I would clear the codes by unhooking the neg. batt. cable for a minute or so and put back on and go for a drive and see if the codes come back.
Is engine idle ok, steady at 650 or 700?
Thread Starter
Intermediate
Joined: May 2008
Posts: 25
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From: Greenwood,,,,Ar 1991 Coupe
If it´s ECM codes you´re talking about then 33 stands for manifold absolute pressure (MAP) sensor circuit (signal voltage high-low vacuum).
Code 41 stands for cylinder select error (faulty or incorrect MEM-CAL)
Both cases were H (history) for you. I would clear the codes by unhooking the neg. batt. cable for a minute or so and put back on and go for a drive and see if the codes come back.
Is engine idle ok, steady at 650 or 700?
Code 41 stands for cylinder select error (faulty or incorrect MEM-CAL)
Both cases were H (history) for you. I would clear the codes by unhooking the neg. batt. cable for a minute or so and put back on and go for a drive and see if the codes come back.
Is engine idle ok, steady at 650 or 700?
I erased the codes after I originally read them, now I'm only getting
1. H41,H72,H74
4. ---
When the SES is not on the engine idles and runs Great.
1.0
Thread Starter
Intermediate
Joined: May 2008
Posts: 25
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From: Greenwood,,,,Ar 1991 Coupe
I can't get my '94 to light up H41 again, like it did when I took a short trip last week. It will probably wait till I'm on the road again.
I got about 11 pages of FSM/AllDATA for H41, but again, mine's a '94. If it's good for a '91 too, I'll get 'em scanned and posted up.
See what you can find out on '91 vs '94...
I got about 11 pages of FSM/AllDATA for H41, but again, mine's a '94. If it's good for a '91 too, I'll get 'em scanned and posted up.
See what you can find out on '91 vs '94...
I know that the ECM's are different on a 94 v/s 91 but other than that I'm not sure.
Pro
Joined: May 2006
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There is another way to erase codes.
CCM-codes:
Ground pin G (with ign. off)
Ignition on, speedo goes blank and then shows 1.0
Press trip/odo untill it shows 1.7
Press and hold eng/met untill it shows ---
Turn ign. off and on to verify codes cleared, shows ---
ECM-codes:
Ground pin G (with ign. off)
Ignition on, speedo goes blank and then shows 1.0
Press TRIP/RESET untill it shows 4.0
Press trip/odo untill it shows 4.7
Press and hold eng/met untill it shows ---
Turn ign. off and on to verify codes cleared, shows ---
And off again to remove the clip in both cases...
If those history codes came on in the 1.1 module then,
H33 stands for: Data clock circuit shorted to B+ ccm internal open
H72 stands for: Lcd dimming output circuit open or shorted to ground
H74 stsnds for: Led dimming output circuit open or shorted to ground
Now here´s at far as it goes for me, don´t quite know this with "data clock" but what I see from it it´s CCM related.
CCM-codes:
Ground pin G (with ign. off)
Ignition on, speedo goes blank and then shows 1.0
Press trip/odo untill it shows 1.7
Press and hold eng/met untill it shows ---
Turn ign. off and on to verify codes cleared, shows ---
ECM-codes:
Ground pin G (with ign. off)
Ignition on, speedo goes blank and then shows 1.0
Press TRIP/RESET untill it shows 4.0
Press trip/odo untill it shows 4.7
Press and hold eng/met untill it shows ---
Turn ign. off and on to verify codes cleared, shows ---
And off again to remove the clip in both cases...
If those history codes came on in the 1.1 module then,
H33 stands for: Data clock circuit shorted to B+ ccm internal open
H72 stands for: Lcd dimming output circuit open or shorted to ground
H74 stsnds for: Led dimming output circuit open or shorted to ground
Now here´s at far as it goes for me, don´t quite know this with "data clock" but what I see from it it´s CCM related.
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Safety Car
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From: :45 minutes from everywhere / E-I-E-I-O
http://members.iatn.net/techmail/vie...Date=yesterday
Looks like a '91 with h41, but ya' gotta' register for viewing... The link doesn't say if it's the same dtc as '94 h41.
Looks like a '91 with h41, but ya' gotta' register for viewing... The link doesn't say if it's the same dtc as '94 h41.
Thread Starter
Intermediate
Joined: May 2008
Posts: 25
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From: Greenwood,,,,Ar 1991 Coupe
http://members.iatn.net/techmail/vie...Date=yesterday
Looks like a '91 with h41, but ya' gotta' register for viewing... The link doesn't say if it's the same dtc as '94 h41.
Looks like a '91 with h41, but ya' gotta' register for viewing... The link doesn't say if it's the same dtc as '94 h41.
Safety Car
Joined: Oct 2007
Posts: 3,816
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From: :45 minutes from everywhere / E-I-E-I-O
