Derale fan wiring, please check
10-22-2021, 08:02 AM
#1
Derale fan wiring, please check I recently installed two Derale pusher fans to help me with my high engine temps I have also replaced the car battery since it had a dead cell. As well as had the stock alternator upgraded for 172 Amps from a reputable shop due to the high current draw of the fans, my dual fuel pumps, and the possibility of updated stereo next year.
Upon starting the car the dash reads about 14 volts, however, once the fans kick in the needle drops down under 13 volts in the yellow hashed area.
Can someone verify my wiring? Using Derale Dual Electric Fan Relay Harness Part# 16765 and Derale High output fan Part# 16925
FAN#1
Battery Power from the Post on the Fuse panel, then to the Red Wire (Pin 30) of #1 Relay.
Chassis ground to Black wire (Pin 86) of #1 Relay.
Green A/C trigger (Pin 85) wire terminated and heat-shrunk.
The yellow wire (Pin 85) to Factory trigger for stock L fan.
Orange wire (Pin 87) to 30 Amp fuse to Blue wire on Derale L Fan.
Negative Fan wire (Black) to Factory L fan ground wire.
FAN#2
Battery Power from the Post on the Fuse panel, then to Red Wire (Pin 30) of #2 Relay.
Chassis ground to Black wire (Pin 86) of #2 Relay.
Green A/C trigger (Pin 85) wire terminated and heat-shrunk.
The yellow wire (Pin 85) to Factory trigger for stock R fan.
Orange wire (Pin 87) to 30 Amp fuse to Blue wire on Derale R fan.
Negative Fan wire (Black) to Factory R fan ground wire.
Using factory wiring allows me to have the PCM command on and off temps of fans, which works correctly. Also, when the A/C compressor is engaged the 2nd fan triggers on regardless of engine temp.
Upon starting the car the dash reads about 14 volts, however, once the fans kick in the needle drops down under 13 volts in the yellow hashed area.
Can someone verify my wiring? Using Derale Dual Electric Fan Relay Harness Part# 16765 and Derale High output fan Part# 16925
FAN#1
Battery Power from the Post on the Fuse panel, then to the Red Wire (Pin 30) of #1 Relay.
Chassis ground to Black wire (Pin 86) of #1 Relay.
Green A/C trigger (Pin 85) wire terminated and heat-shrunk.
The yellow wire (Pin 85) to Factory trigger for stock L fan.
Orange wire (Pin 87) to 30 Amp fuse to Blue wire on Derale L Fan.
Negative Fan wire (Black) to Factory L fan ground wire.
FAN#2
Battery Power from the Post on the Fuse panel, then to Red Wire (Pin 30) of #2 Relay.
Chassis ground to Black wire (Pin 86) of #2 Relay.
Green A/C trigger (Pin 85) wire terminated and heat-shrunk.
The yellow wire (Pin 85) to Factory trigger for stock R fan.
Orange wire (Pin 87) to 30 Amp fuse to Blue wire on Derale R fan.
Negative Fan wire (Black) to Factory R fan ground wire.
Using factory wiring allows me to have the PCM command on and off temps of fans, which works correctly. Also, when the A/C compressor is engaged the 2nd fan triggers on regardless of engine temp.
10-22-2021, 08:50 AM
#2
TECH Fanatic
iTrader: (13)
I recently installed two Derale pusher fans to help me with my high engine temps I have also replaced the car battery since it had a dead cell. As well as had the stock alternator upgraded for 172 Amps from a reputable shop due to the high current draw of the fans, my dual fuel pumps, and the possibility of updated stereo next year.
Upon starting the car the dash reads about 14 volts, however, once the fans kick in the needle drops down under 13 volts in the yellow hashed area.
Can someone verify my wiring? Using Derale Dual Electric Fan Relay Harness Part# 16765 and Derale High output fan Part# 16925
FAN#1
Battery Power from the Post on the Fuse panel, then to the Red Wire (Pin 30) of #1 Relay.
Chassis ground to Black wire (Pin 86) of #1 Relay.
Green A/C trigger (Pin 85) wire terminated and heat-shrunk.
The yellow wire (Pin 85) to Factory trigger for stock L fan.
Orange wire (Pin 87) to 30 Amp fuse to Blue wire on Derale L Fan.
Negative Fan wire (Black) to Factory L fan ground wire.
FAN#2
Battery Power from the Post on the Fuse panel, then to Red Wire (Pin 30) of #2 Relay.
Chassis ground to Black wire (Pin 86) of #2 Relay.
Green A/C trigger (Pin 85) wire terminated and heat-shrunk.
The yellow wire (Pin 85) to Factory trigger for stock R fan.
Orange wire (Pin 87) to 30 Amp fuse to Blue wire on Derale R fan.
Negative Fan wire (Black) to Factory R fan ground wire.
Using factory wiring allows me to have the PCM command on and off temps of fans, which works correctly. Also, when the A/C compressor is engaged the 2nd fan triggers on regardless of engine temp.
Upon starting the car the dash reads about 14 volts, however, once the fans kick in the needle drops down under 13 volts in the yellow hashed area.
Can someone verify my wiring? Using Derale Dual Electric Fan Relay Harness Part# 16765 and Derale High output fan Part# 16925
FAN#1
Battery Power from the Post on the Fuse panel, then to the Red Wire (Pin 30) of #1 Relay.
Chassis ground to Black wire (Pin 86) of #1 Relay.
Green A/C trigger (Pin 85) wire terminated and heat-shrunk.
The yellow wire (Pin 85) to Factory trigger for stock L fan.
Orange wire (Pin 87) to 30 Amp fuse to Blue wire on Derale L Fan.
Negative Fan wire (Black) to Factory L fan ground wire.
FAN#2
Battery Power from the Post on the Fuse panel, then to Red Wire (Pin 30) of #2 Relay.
Chassis ground to Black wire (Pin 86) of #2 Relay.
Green A/C trigger (Pin 85) wire terminated and heat-shrunk.
The yellow wire (Pin 85) to Factory trigger for stock R fan.
Orange wire (Pin 87) to 30 Amp fuse to Blue wire on Derale R fan.
Negative Fan wire (Black) to Factory R fan ground wire.
Using factory wiring allows me to have the PCM command on and off temps of fans, which works correctly. Also, when the A/C compressor is engaged the 2nd fan triggers on regardless of engine temp.
10-22-2021, 11:57 AM
#4
TECH Addict
The dash volt meter will always dump low due to al the parasitic competing loads ,, I would add a power block with Fuse that is sourced off the battery +,
you can buy them with 2,4,6,8 fuses. This block would be where you feed the red wires to the relay. The Fuse on the power block is normally 80-100A.
It insures the fans get full power and doesn't piggyback them on to your factory harness which if like most is old, tired and wasn't built that heavy duty to begin with.
The fuses Deralle recommends provide the protection for a bad fan, the Block fuse is for failures of a more major level.
FWIW,, The 30A relays are "ok" for fans, 50's are better they have bigger contacts internally and have less voltage drop.
I use #12 or #10 wire for fan circuits. Less resistance means less wasted energy.
you can buy them with 2,4,6,8 fuses. This block would be where you feed the red wires to the relay. The Fuse on the power block is normally 80-100A.
It insures the fans get full power and doesn't piggyback them on to your factory harness which if like most is old, tired and wasn't built that heavy duty to begin with.
The fuses Deralle recommends provide the protection for a bad fan, the Block fuse is for failures of a more major level.
FWIW,, The 30A relays are "ok" for fans, 50's are better they have bigger contacts internally and have less voltage drop.
I use #12 or #10 wire for fan circuits. Less resistance means less wasted energy.
10-22-2021, 02:31 PM
#5
The PCM fan outputs and the AC pressure switches (almost) always provide ground to trigger the relays.
I think you need the other wires on the relay coil to go to power, not ground. A small fuse (5A, tops, maybe 2A) is sufficient to provide power to two relays. And for most relays, the coil isn't polarized, so either wire can be power and the other can be ground. So you can just put power on the black wires if you want. No need to swap everything around.
I think you need the other wires on the relay coil to go to power, not ground. A small fuse (5A, tops, maybe 2A) is sufficient to provide power to two relays. And for most relays, the coil isn't polarized, so either wire can be power and the other can be ground. So you can just put power on the black wires if you want. No need to swap everything around.
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pdxmotorhead (10-22-2021)
10-23-2021, 10:31 AM
#7
The PCM fan outputs and the AC pressure switches (almost) always provide ground to trigger the relays.
I think you need the other wires on the relay coil to go to power, not ground. A small fuse (5A, tops, maybe 2A) is sufficient to provide power to two relays. And for most relays, the coil isn't polarized, so either wire can be power and the other can be ground. So you can just put power on the black wires if you want. No need to swap everything around.
I think you need the other wires on the relay coil to go to power, not ground. A small fuse (5A, tops, maybe 2A) is sufficient to provide power to two relays. And for most relays, the coil isn't polarized, so either wire can be power and the other can be ground. So you can just put power on the black wires if you want. No need to swap everything around.
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10-26-2021, 10:48 AM
#8
I did notice the differences in the wiring diagrams provided for the fans themselves vs. the relays. Are you recommending to swap 86 and 85 and this could fix my problem?
Really hoping to get this sorted before I put the car away for the winter.
10-26-2021, 10:57 AM
#9
No, simply reversing 85 and 86 is unlikely to make any difference. I was merely following the suggestion by Racer-X- that you might need to provide power to the relay coil and that the black wires would already be on the correct terminals if you used them to provide that power.
The choice between using 85 or 86 for power vs ground is mostly moot - either way will work. However, putting power on 86 and ground on 85 will make the relay last a little bit longer because of the internal diode.
The choice between using 85 or 86 for power vs ground is mostly moot - either way will work. However, putting power on 86 and ground on 85 will make the relay last a little bit longer because of the internal diode.
10-26-2021, 01:05 PM
#10
No, simply reversing 85 and 86 is unlikely to make any difference. I was merely following the suggestion by Racer-X- that you might need to provide power to the relay coil and that the black wires would already be on the correct terminals if you used them to provide that power.
The choice between using 85 or 86 for power vs ground is mostly moot - either way will work. However, putting power on 86 and ground on 85 will make the relay last a little bit longer because of the internal diode.
The choice between using 85 or 86 for power vs ground is mostly moot - either way will work. However, putting power on 86 and ground on 85 will make the relay last a little bit longer because of the internal diode.
10-26-2021, 05:47 PM
#11
Ok, had a few minutes to run a test. Here are the numbers below.
12.47 battery (car not started for 2 weeks)
14.55 running, nothing else on..
13.68 1 fan lights radio
13.05 2 fans, lights, radio
12.42 2 fans, lights, radio, ac
Do I need to take the alternator back and tell them its messed up? I would have thought that it would have been able to keep the voltage as close to 14 volts with loads added. Or, do I need to upgrade the Big3 for the voltage?
12.47 battery (car not started for 2 weeks)
14.55 running, nothing else on..
13.68 1 fan lights radio
13.05 2 fans, lights, radio
12.42 2 fans, lights, radio, ac
Do I need to take the alternator back and tell them its messed up? I would have thought that it would have been able to keep the voltage as close to 14 volts with loads added. Or, do I need to upgrade the Big3 for the voltage?
10-27-2021, 07:48 AM
#12
Are those voltages at idle? Or at 1500-2000 RPM's?
And is this a CS-130D alternator? Those aren't the strongest at idle speed. You may need a stronger, more modern alternator with a higher current capacity.
An AD-244 unit of 140+ amps from a Suburban, Tahoe or Yukon might work for you.
And is this a CS-130D alternator? Those aren't the strongest at idle speed. You may need a stronger, more modern alternator with a higher current capacity.
An AD-244 unit of 140+ amps from a Suburban, Tahoe or Yukon might work for you.
Last edited by Racer-X-; 10-27-2021 at 07:56 AM.
10-27-2021, 10:17 AM
#13
Are those voltages at idle? Or at 1500-2000 RPM's?
And is this a CS-130D alternator? Those aren't the strongest at idle speed. You may need a stronger, more modern alternator with a higher current capacity.
An AD-244 unit of 140+ amps from a Suburban, Tahoe or Yukon might work for you.
And is this a CS-130D alternator? Those aren't the strongest at idle speed. You may need a stronger, more modern alternator with a higher current capacity.
An AD-244 unit of 140+ amps from a Suburban, Tahoe or Yukon might work for you.
10-30-2021, 07:05 PM
#14
The issue with low voltage/low current at idle is kind of inherent in the design. The increased current is maximum current at some higher RPMs. CS-130D alternators lose a lot of performance at idle speeds, compared to their maximum current ratings at higher RPMs. The CS-130Ds are better than the older 10si/12si units, but they don't perform as well at idle as the newer designs.
11-02-2021, 07:47 AM
#15
First, check your voltages with the thing running 1500-2000 RPMs with no load (Park or neutral). See whether those voltages rise up to the 13.5-14.5 volt range. I suspect they will, especially with the alternator reworked for the higher current.
The issue with low voltage/low current at idle is kind of inherent in the design. The increased current is maximum current at some higher RPMs. CS-130D alternators lose a lot of performance at idle speeds, compared to their maximum current ratings at higher RPMs. The CS-130Ds are better than the older 10si/12si units, but they don't perform as well at idle as the newer designs.
The issue with low voltage/low current at idle is kind of inherent in the design. The increased current is maximum current at some higher RPMs. CS-130D alternators lose a lot of performance at idle speeds, compared to their maximum current ratings at higher RPMs. The CS-130Ds are better than the older 10si/12si units, but they don't perform as well at idle as the newer designs.