95 z28 Fans not coming on and what scanner to buy?
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95 z28 Fans not coming on and what scanner to buy?
I have a 95 z28 lt1 6 speed camaro that I pulled out of a field after sitting 3+ years. I got the car running again with a new fuel pump and now the fans dont kick on. The previous owner im guessing had one of the fans wired up with a toggle switch and im trying to eliminate this. What I have done:
Replaced all 3 fan relays and fuse's
Jumped the 5 and 6 connection on the DLC - Fans Turn on
New water pump sensor
Checked the ground, black wire off the WP sensor and it is a good ground. Also check the yellow wire for the +5volts, it has 5.01volts so that is good.
I looked for a PCM BAT fuse but didnt see one, but did pull the PCM and PCM IGN fuse for 30 seconds with the key off.
From what I have read, I need to have it scanned, so my question is:
I see alot of scanners for sale on ebay, Which one do you suggest that I get? type/brand?
And if this could be a PCM problem, where is the PCM ground located at on the car body and where would this pcm bat fuse be located if not in the fuse box in the car or relay box under the hood.
Thanks.
Replaced all 3 fan relays and fuse's
Jumped the 5 and 6 connection on the DLC - Fans Turn on
New water pump sensor
Checked the ground, black wire off the WP sensor and it is a good ground. Also check the yellow wire for the +5volts, it has 5.01volts so that is good.
I looked for a PCM BAT fuse but didnt see one, but did pull the PCM and PCM IGN fuse for 30 seconds with the key off.
From what I have read, I need to have it scanned, so my question is:
I see alot of scanners for sale on ebay, Which one do you suggest that I get? type/brand?
And if this could be a PCM problem, where is the PCM ground located at on the car body and where would this pcm bat fuse be located if not in the fuse box in the car or relay box under the hood.
Thanks.
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Re: 95 z28 Fans not coming on and what scanner to buy?
ok, got a scanner and my coolant temp is reading properly. It will even get up to 200 degrease and still no fans. I did check the signal wire from the pcm to the relays, both of them, and they are good. I can jumper the relay at the relay box under the hood and the fan kicks on so I know they are good. Bad PCM? Is there a way to check to see what the pcm has programmed into it to tell it when to kick the fans on?
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From: Little Rock, AR
Re: 95 z28 Fans not coming on and what scanner to buy?
ok, got a scanner and my coolant temp is reading properly. It will even get up to 200 degrease and still no fans. I did check the signal wire from the pcm to the relays, both of them, and they are good. I can jumper the relay at the relay box under the hood and the fan kicks on so I know they are good. Bad PCM? Is there a way to check to see what the pcm has programmed into it to tell it when to kick the fans on?
4th Gen LT1 F-body Tech Articles
Fans won't come on with the a/c if the system is inhibited because of lack of charge.
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what are you scanning with? I am not certain if there are other ways to check what your settings are(given they are not the factory settings and they probably are) but if you have the cable and laptop and software you can read the pcm and then open that information up and see. If you have that software and whatnot then you also most likely can change the turn on temps and reflash the pcm. Are you overheating or just concerned? I personally like lower turn on temps than stock settings and I also liked a manual override switch that still allows the pcm control but lets me switch the fans on if I want to(I havent had the need to use it since I cleaned all the debri out of radiator and condensor fins and installed a 160 stat and have fan settings down.
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Re: 95 z28 Fans not coming on and what scanner to buy?
Thanks for pointing that out to me Shoebox, I went through your troubleshooting guild about 4 times and somehow passed that up. Now that I let the temp get to 226, Fan 1 did turn on and at 235 Fan 2 turned on. I do remember seeing about the gauge being within 10-15 degrees off and Im guessing that is the problem with this car. At 226, it barley hits the red and at 235 its entering the red area on the gauge. Is that normal or is my gauge off?
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Re: 95 z28 Fans not coming on and what scanner to buy?
what are you scanning with? I am not certain if there are other ways to check what your settings are(given they are not the factory settings and they probably are) but if you have the cable and laptop and software you can read the pcm and then open that information up and see. If you have that software and whatnot then you also most likely can change the turn on temps and reflash the pcm. Are you overheating or just concerned? I personally like lower turn on temps than stock settings and I also liked a manual override switch that still allows the pcm control but lets me switch the fans on if I want to(I havent had the need to use it since I cleaned all the debri out of radiator and condensor fins and installed a 160 stat and have fan settings down.
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Re: 95 z28 Fans not coming on and what scanner to buy?
Thanks for pointing that out to me Shoebox, I went through your troubleshooting guild about 4 times and somehow passed that up. Now that I let the temp get to 226, Fan 1 did turn on and at 235 Fan 2 turned on. I do remember seeing about the gauge being within 10-15 degrees off and Im guessing that is the problem with this car. At 226, it barley hits the red and at 235 its entering the red area on the gauge. Is that normal or is my gauge off?
Rob also has a guide to checking your coolant temp sensor accuracy:
4th Gen LT1 F-body Tech Articles
You should check both the gauge sensor in the driver's side head, and the sensor for the PCM in the water pump housing.
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From: idaho
Originally Posted by war_hawk99
Quote:
Originally Posted by slick1hunting
what are you scanning with? I am not certain if there are other ways to check what your settings are(given they are not the factory settings and they probably are) but if you have the cable and laptop and software you can read the pcm and then open that information up and see. If you have that software and whatnot then you also most likely can change the turn on temps and reflash the pcm. Are you overheating or just concerned? I personally like lower turn on temps than stock settings and I also liked a manual override switch that still allows the pcm control but lets me switch the fans on if I want to(I havent had the need to use it since I cleaned all the debri out of radiator and condensor fins and installed a 160 stat and have fan settings down.
Posted from Camaroz28.com App for Android
The program im using is TunerPro Rt. Im using the free version that just allows you to scan and view the data. It does have a paid version that the free version allows you to see what you would get in the paid version, But I dont see anywhere in the paid versions options to view the Fan kick on temp. The only thing it has for fans is the options for kick on/off at MPH speeds. What program do you use to lower your temp fan kick on? Im not overheating yet, just concerned. Another program I tried was DataMaster, but I cant get it to connect to the pcm for some reason.
Originally Posted by slick1hunting
what are you scanning with? I am not certain if there are other ways to check what your settings are(given they are not the factory settings and they probably are) but if you have the cable and laptop and software you can read the pcm and then open that information up and see. If you have that software and whatnot then you also most likely can change the turn on temps and reflash the pcm. Are you overheating or just concerned? I personally like lower turn on temps than stock settings and I also liked a manual override switch that still allows the pcm control but lets me switch the fans on if I want to(I havent had the need to use it since I cleaned all the debri out of radiator and condensor fins and installed a 160 stat and have fan settings down.
Posted from Camaroz28.com App for Android
The program im using is TunerPro Rt. Im using the free version that just allows you to scan and view the data. It does have a paid version that the free version allows you to see what you would get in the paid version, But I dont see anywhere in the paid versions options to view the Fan kick on temp. The only thing it has for fans is the options for kick on/off at MPH speeds. What program do you use to lower your temp fan kick on? Im not overheating yet, just concerned. Another program I tried was DataMaster, but I cant get it to connect to the pcm for some reason.
Posted from Camaroz28.com App for Android
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Re: 95 z28 Fans not coming on and what scanner to buy?
In a 95, both fans should come on low speed at 226*F, then bump up to high speed at 235*F, as described in Rob's guide. Only the 93 and very early 94 models had the Fan #1/Fan #2 setup. My late 94 has both low/both high.
Rob also has a guide to checking your coolant temp sensor accuracy:
4th Gen LT1 F-body Tech Articles
You should check both the gauge sensor in the driver's side head, and the sensor for the PCM in the water pump housing.
Rob also has a guide to checking your coolant temp sensor accuracy:
4th Gen LT1 F-body Tech Articles
You should check both the gauge sensor in the driver's side head, and the sensor for the PCM in the water pump housing.
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Joined: May 2013
Posts: 9
Re: 95 z28 Fans not coming on and what scanner to buy?
I believe the fan turn on adjustments are in the tables section of what I use(jet) should be similar in tunercats. I am guessing none of the logging software will read the pcm or flash it and not sure if the tunerpro does that or what the options are for the obd1 cars other than tunercats. Here is a link that will give you some info and it has links to the various software. LT1 PCM Tuning - Tips & Tricks for DIY Tuning!
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From: Little Rock, AR
Re: 95 z28 Fans not coming on and what scanner to buy?
In Tunercat look in the tables to adjust the fan on temperature. The "Fan Enable Coolant Temp Vs. Speed" table in the middle column about halfway down is the one you want.
If your fans are coming on at the stock temperatures, and your car is still overheating, you probably have a problem that changing the fan on temperatures isn't going to fix.
If your fans are coming on at the stock temperatures, and your car is still overheating, you probably have a problem that changing the fan on temperatures isn't going to fix.
Thread Starter
Registered User
Joined: May 2013
Posts: 9
Re: 95 z28 Fans not coming on and what scanner to buy?
In Tunercat look in the tables to adjust the fan on temperature. The "Fan Enable Coolant Temp Vs. Speed" table in the middle column about halfway down is the one you want.
If your fans are coming on at the stock temperatures, and your car is still overheating, you probably have a problem that changing the fan on temperatures isn't going to fix.
If your fans are coming on at the stock temperatures, and your car is still overheating, you probably have a problem that changing the fan on temperatures isn't going to fix.