Help with codes
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Joined: Feb 2011
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Help with codes
I have a 95 that gets an occasional service soon light. It generally happens after the car kind of lurches. I haven't really been able to nail it down to when it happens, but I think it is between deceleration and re-accelerating at slower speeds. It happens so fast, it takes me by surprise. Anyway, the light comes on for a few miles and then turns off after the lurch. Yesterday, while coming to work, the light was on for the entire drive (highway driving and I did not notice a lurch), so I used the paperclip to pull the codes and got an H25 on module 1 and an H48 on Module 4. 9 and A were ---.
Diagnoses and remedy ideas? I'm nowhere near a gearhead, but more than willing to turn a wrench. The extent of my knowledge ends at replacing brakes, oil and such, although I did just replace the clutch master and slave cylinder. So, layman's terms would be really helpful.
Thanks-
Diagnoses and remedy ideas? I'm nowhere near a gearhead, but more than willing to turn a wrench. The extent of my knowledge ends at replacing brakes, oil and such, although I did just replace the clutch master and slave cylinder. So, layman's terms would be really helpful.
Thanks-
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,008
From: Texas
I have a 95 that gets an occasional service soon light. It generally happens after the car kind of lurches. I haven't really been able to nail it down to when it happens, but I think it is between deceleration and re-accelerating at slower speeds. It happens so fast, it takes me by surprise. Anyway, the light comes on for a few miles and then turns off after the lurch. Yesterday, while coming to work, the light was on for the entire drive (highway driving and I did not notice a lurch), so I used the paperclip to pull the codes and got an H25 on module 1 and an H48 on Module 4. 9 and A were ---.
Diagnoses and remedy ideas? I'm nowhere near a gearhead, but more than willing to turn a wrench. The extent of my knowledge ends at replacing brakes, oil and such, although I did just replace the clutch master and slave cylinder. So, layman's terms would be really helpful.
Thanks-
Diagnoses and remedy ideas? I'm nowhere near a gearhead, but more than willing to turn a wrench. The extent of my knowledge ends at replacing brakes, oil and such, although I did just replace the clutch master and slave cylinder. So, layman's terms would be really helpful.
Thanks-
DTC 48 - Mass Air Flow (MAF) Sensor Circuit
Check the connection to the MAF sensor
Clean the MAF sensor wires using some contact cleaner. Do NOT touch the wires. The wires accumulate oil over time which leads to poor metering and performance.
Le Mans Master
Joined: Jan 2006
Posts: 5,620
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From: Orlando FL
Also it might be best to get "throttle body and air intake" cleaner it's designed not to do any damage to the MAF and the wire and resistor unit that is suspended.
Never really examined the contents of the throttle cleaner compared to a basic cleaner. But I read enough about it and I would rather be safe on a expensive piece like the MAF sensor.
Last edited by pcolt94; Jul 12, 2012 at 10:02 PM.
Race Director
Joined: Apr 2000
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From: Texas
Race Director
Joined: Apr 2002
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From: Anaheim CA
There is a list of the error codes and what they mean here:
http://forums.corvetteforum.com/1576116036-post35.html
http://forums.corvetteforum.com/1576116036-post35.html
Drifting
Joined: Mar 2012
Posts: 1,492
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From: New Jersey
H25 on Module 1 is courtesy lamp coil circuit open or shorted to ground. It is a CCM (Central control module) code and has nothing to do H48 in module 4, a PCM (Powertrain Control Module) code.
H just denotes that it is a history code meaning it is not present at this time - it has occurred in the past but is not presently occuring. C would denote a current fault code.
H just denotes that it is a history code meaning it is not present at this time - it has occurred in the past but is not presently occuring. C would denote a current fault code.
Last edited by Silver96ce; Jul 13, 2012 at 01:44 AM.
