wire identification help!
Thread Starter
Pro
Joined: Aug 2007
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From: Mississippi
wire identification help!
1987 convertible with AUX fan option. The PO had the fans wired in hot and I am trying to get the wiring back to factory and need help with identifying these wires. I know they go to the Fan Relay but cant determine why I have 3 red wires as shown in the first pic.
The second pic has a cut wire coming off the positive battery cable and another red wire with a connection. This red wire goes to a thermal block? and then turns orange. This is the wire the PO had going to the Fan.
Anyway thanks for any help.
Mike
The second pic has a cut wire coming off the positive battery cable and another red wire with a connection. This red wire goes to a thermal block? and then turns orange. This is the wire the PO had going to the Fan.
Anyway thanks for any help.
Mike
Last edited by mkh; Aug 18, 2015 at 07:31 PM.
Drifting
Joined: May 2003
Posts: 1,979
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From: Lakeport CA
Ditto... a year & I'll check the FSM... I have 7 diff years of C4 books...
I highly recommend you but the set for your year. Takes awhile to learn how to use them but everything is there for fixing anything.
A quick look at 88 book shows:
blk/red - relay output to cooling fan (hot/power supply)
Red - power (hot at all times from battery junction) with fusible link
green/white - relay coil ground from ECM fan control circuit
Drk Blue - fused cooling fan power (hot in run only)
Since your year might be diff, the other red may be the fused/hot in run. Also if you have the Aux fan in the front of the radiator, the second red would also be a source power from battery junction block (behind/below battery) and runs the second relay, which also has a green/white control ground but is from the temp switch in the right rear cyl head.
I highly recommend you but the set for your year. Takes awhile to learn how to use them but everything is there for fixing anything.
A quick look at 88 book shows:
blk/red - relay output to cooling fan (hot/power supply)
Red - power (hot at all times from battery junction) with fusible link
green/white - relay coil ground from ECM fan control circuit
Drk Blue - fused cooling fan power (hot in run only)
Since your year might be diff, the other red may be the fused/hot in run. Also if you have the Aux fan in the front of the radiator, the second red would also be a source power from battery junction block (behind/below battery) and runs the second relay, which also has a green/white control ground but is from the temp switch in the right rear cyl head.
Last edited by Trog; Aug 18, 2015 at 07:08 PM.
Thread Starter
Pro
Joined: Aug 2007
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From: Mississippi
Updated the year and optional fan.
What about the second picture the short red wire is only about 2 inches long and then it is cut. it comes straight from the positive battery post. The second picture also shows a red wire with a connection it goes from red to orange and goes into the wiring harness. I do have all the FSM manuals ordered.
Thanks.
What about the second picture the short red wire is only about 2 inches long and then it is cut. it comes straight from the positive battery post. The second picture also shows a red wire with a connection it goes from red to orange and goes into the wiring harness. I do have all the FSM manuals ordered.
Thanks.
Team Owner
Joined: Sep 2003
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Updated the year and optional fan.
What about the second picture the short red wire is only about 2 inches long and then it is cut. it comes straight from the positive battery post. The second picture also shows a red wire with a connection it goes from red to orange and goes into the wiring harness. I do have all the FSM manuals ordered.
Thanks.
What about the second picture the short red wire is only about 2 inches long and then it is cut. it comes straight from the positive battery post. The second picture also shows a red wire with a connection it goes from red to orange and goes into the wiring harness. I do have all the FSM manuals ordered.
Thanks.
Snapshots of what you have are next to useless without a person having a "hands on" - I can confirm that what's been mentioned for the cooling fans is correct but you've a multitude of choices for various others.
Thread Starter
Pro
Joined: Aug 2007
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From: Mississippi
Yes I agree I need the FSM's. Car was running fine and I just decided to go ahead and start to fix the cooling fans. I cut the old relay out and that is the wires you see coming out of the harness. To late not to cause other problems. Car wont start now
The PO had a wire from the fan to the blue wire (which is hot) and to the connector pigtail shown in the second picture down behind the battery. I assume when I removed the wiring I killed the power to something which is causing the no-start.
The PO had a wire from the fan to the blue wire (which is hot) and to the connector pigtail shown in the second picture down behind the battery. I assume when I removed the wiring I killed the power to something which is causing the no-start.
Team Owner
Joined: Jan 2003
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From: Summerland B.C. Canada
Leaving the pos cable terminal, should be a large red going to junction block and another large red going to a barrel shaped splice. Where that large red enters splice, should be a smaller red, that goes to ECM power connector.
On the bottom of the slice, should be 2 orange fusible links that power the fans, via the 2 fan relays.
Ignore the DPDT switch and red wires, thats for running a manual switch. The rest of the info and colors should be correct.
http://members.shaw.ca/agent86/85%20Cooling%20Fan.gif
On the bottom of the slice, should be 2 orange fusible links that power the fans, via the 2 fan relays.
Ignore the DPDT switch and red wires, thats for running a manual switch. The rest of the info and colors should be correct.
http://members.shaw.ca/agent86/85%20Cooling%20Fan.gif
Drifting
Joined: May 2003
Posts: 1,979
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From: Lakeport CA
Agent 86 has given you the wiring diagram from FSM (with his added override switch that you should ignore unless you want to add it).
You probably shouldn't have cut out the relays, you still need them, just wired up correctly. And other poster is correct, that power feed from the battery should go to ECM. That single connector is a way to kill power to ECM & clear DTC codes on those years.
You need to find someone with a close year, 86/87/88 and take a look at it in order to really see how it came from factory.
You probably shouldn't have cut out the relays, you still need them, just wired up correctly. And other poster is correct, that power feed from the battery should go to ECM. That single connector is a way to kill power to ECM & clear DTC codes on those years.
You need to find someone with a close year, 86/87/88 and take a look at it in order to really see how it came from factory.
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Thread Starter
Pro
Joined: Aug 2007
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From: Mississippi
Agent 86 has given you the wiring diagram from FSM (with his added override switch that you should ignore unless you want to add it).
You probably shouldn't have cut out the relays, you still need them, just wired up correctly. And other poster is correct, that power feed from the battery should go to ECM. That single connector is a way to kill power to ECM & clear DTC codes on those years.
You need to find someone with a close year, 86/87/88 and take a look at it in order to really see how it came from factory.
You probably shouldn't have cut out the relays, you still need them, just wired up correctly. And other poster is correct, that power feed from the battery should go to ECM. That single connector is a way to kill power to ECM & clear DTC codes on those years.
You need to find someone with a close year, 86/87/88 and take a look at it in order to really see how it came from factory.
Thread Starter
Pro
Joined: Aug 2007
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From: Mississippi
An yes I definitely need to look at a similar car. That would help a lot. I believe the PO cut out the fusible links for the Fans. Anyone have a picture of this area on a 87?
Thanks for the help.
Thanks for the help.
Last edited by mkh; Aug 18, 2015 at 10:19 PM.
Race Director
Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
I purchased a new relay and the one the PO had previously installed was a mess. I purchased a new relay and pigtail harness. The following picture with the pigtail junction I have circled is the wire I am almost sure is not letting the car start. This pigtail goes to a small barrel and then into the wiring harness behind the battery. The wire is red up until the barrel and then is orange.
I believe the connector you circled is the ECM power connector. Your "barrel" is the splice between the fusible link and the usual wiring. This connector also supplies power to the fuel pump, as in this diagram:
Team Owner
Joined: Jan 2003
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From: Summerland B.C. Canada
Pic 1
3 reds= 2 went to 2 orange fusible links via a connector
The other red is power for main fan. It will be the other end of one of the 2 other red wires.
Pic 2
That connector is for ECM power, that's why she no start.
Add the end to that taped red in pic and she should start.
3 reds= 2 went to 2 orange fusible links via a connector
The other red is power for main fan. It will be the other end of one of the 2 other red wires.
Pic 2
That connector is for ECM power, that's why she no start.
Add the end to that taped red in pic and she should start.
Team Owner
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I have the '87 FSM but his are ordered and on the way. I believe the OP mentioned fusible links eliminated etc and why NOT just wait and confirm it all.
Thread Starter
Pro
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From: Mississippi
Pic 1
3 reds= 2 went to 2 orange fusible links via a connector
The other red is power for main fan. It will be the other end of one of the 2 other red wires.
Pic 2
That connector is for ECM power, that's why she no start.
Add the end to that taped red in pic and she should start.
3 reds= 2 went to 2 orange fusible links via a connector
The other red is power for main fan. It will be the other end of one of the 2 other red wires.
Pic 2
That connector is for ECM power, that's why she no start.
Add the end to that taped red in pic and she should start.
Thanks for all the help I really appreciate it.
Mike
Team Owner
Joined: Sep 2003
Posts: 25,331
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Ok great. I now know I am missing the fusible links going to the fan relays. I know where the blue, black/red and the green/white wire go. In this picture the wires I have circled are showing continuity does this sound correct?
Thanks for all the help I really appreciate it.
Mike
Thanks for all the help I really appreciate it.
Mike
Team Owner
Joined: Jan 2003
Posts: 20,254
Likes: 221
From: Summerland B.C. Canada
That is my grade 4 drawing of my late 86 power distribution from battery terminal. From what I know, the wiring between 86 and 87 is the virtually the same.
That drawing is almost to scale 😜
And this is my first time taking a pic and uploading from my phone, hope it works 😴
Team Owner
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That is my grade 4 drawing of my late 86 power distribution from battery terminal. From what I know, the wiring between 86 and 87 is the virtually the same.
That drawing is almost to scale ��
And this is my first time taking a pic and uploading from my phone, hope it works ��
That drawing is almost to scale ��
And this is my first time taking a pic and uploading from my phone, hope it works ��
This is from an '87 FSM. FL - D & E are the fans and H is the ECM, MAF relays, OPS and the FPR from a splice. A service + cable would have required the addition of the proper connectors and it is very likely when a cable was replaced and maybe this one was, a short-cut might be to eliminate them. They may very well NOT be there. The image is from 8A-201-1
OP - when you get your FSM see 8A-10-0 for the FL's D, E & H like in this image I gave you a peek at.
Last edited by WVZR-1; Aug 19, 2015 at 10:28 PM.
Thread Starter
Pro
Joined: Aug 2007
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From: Mississippi
That is my grade 4 drawing of my late 86 power distribution from battery terminal. From what I know, the wiring between 86 and 87 is the virtually the same.
That drawing is almost to scale 😜
And this is my first time taking a pic and uploading from my phone, hope it works 😴[/QUOTE]
Yes it works. I am missing everything circled in red. No problem correcting it I just need to make sure I wire it correctly. The picture above this post with the 2 wires circled are showing continuity with my meter. Is that correct? Neither one of them are hot so I assume this is where the fusible links attach to make them hot. That only leaves One red wire that I haven't figured out yet. Its the one on the right in the first picture I posted where the wires come out of the Loom and go to the fan relay.
Thanks again for every ones help.
Mike
That drawing is almost to scale 😜
And this is my first time taking a pic and uploading from my phone, hope it works 😴[/QUOTE]
Yes it works. I am missing everything circled in red. No problem correcting it I just need to make sure I wire it correctly. The picture above this post with the 2 wires circled are showing continuity with my meter. Is that correct? Neither one of them are hot so I assume this is where the fusible links attach to make them hot. That only leaves One red wire that I haven't figured out yet. Its the one on the right in the first picture I posted where the wires come out of the Loom and go to the fan relay.
Thanks again for every ones help.
Mike
Team Owner
Joined: Jan 2003
Posts: 20,254
Likes: 221
From: Summerland B.C. Canada
Ok great. I now know I am missing the fusible links going to the fan relays. I know where the blue, black/red and the green/white wire go. In this picture the wires I have circled are showing continuity does this sound correct?
Thanks for all the help I really appreciate it.
Mike
Thanks for all the help I really appreciate it.
Mike
The third red started from fusible link and goes to secondary side of aux fan relay.
You can verify that by unplugging aux fan relay connector and test for continuity between red in connector and the cut end near battery.
Thread Starter
Pro
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From: Mississippi
Great!!! I now have it all figured out
. Any idea what size fusible link I should purchase to recreate the wiring section I am missing. If I have it all correct the fusible links are just proctecting the fans.
. Any idea what size fusible link I should purchase to recreate the wiring section I am missing. If I have it all correct the fusible links are just proctecting the fans.