Where's the computer and codes?
Safety Car
Joined: Jul 2004
Posts: 3,844
Likes: 30
.....welcome to the jungle....i had an 81 and it was located behind the drivers seat...in my 88, it is located on the passenger side above the dash hush panel......not entirely sure about the 85.....if you plan on keeping the car you should buy a HELMS SERVICE MANUAL.....good luck sir...
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The pics that 86PACER provides shows the ALDL or Assembly Line Diagnostic Link. The car's PCM or powertrain control module is located behind the passenger side dash just in front of and below the so-called "breadbasket"
To effectively do diagnostics, get a copy of the Factory Service Manual (FSM). They occasionally show up in the C4 Parts For Sale section, or you can find them on eBay. You should be able to buy brand new set (typically the FSM is a two-book set) from Helm at www.helminc.com
Helm is the supplier of original service manuals to the dealerships.
To effectively do diagnostics, get a copy of the Factory Service Manual (FSM). They occasionally show up in the C4 Parts For Sale section, or you can find them on eBay. You should be able to buy brand new set (typically the FSM is a two-book set) from Helm at www.helminc.com
Helm is the supplier of original service manuals to the dealerships.
Instructor
Joined: Apr 2007
Posts: 127
Likes: 0
On the 85 the computer is on the firewall behind the foam cushin in front of the pax seat. If you are not a contortionist, remove the dash cover, A/C duct, cushin , then the 4 bolts thst hold the silver box on the firewall. The other silver box is the burn off module.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
oh, dear... this is getting unnecessarily complex.
First off, it's not a Powertrain Control Module - it does nada for the tranny, it's simply a ECU - Engine Control Unit.
Rick - Move the passengers seat all the way back. remove the lower plastic panel - black with the floor lite. Bend over backwards and a few other directions and look up... with your head against the fire wall... yea, it's a bitch, but it's the best way to get it.
from there, look straight up. You will see a white piece of nylon with two 10mm bolts. Those are what hold the ECU in the bracket. Remove bolts, pull down. ECU is now out. Technically, you can't see the ECU until you remove it. There is a black plastic cover that shields it from view.
First off, it's not a Powertrain Control Module - it does nada for the tranny, it's simply a ECU - Engine Control Unit.
Rick - Move the passengers seat all the way back. remove the lower plastic panel - black with the floor lite. Bend over backwards and a few other directions and look up... with your head against the fire wall... yea, it's a bitch, but it's the best way to get it.
from there, look straight up. You will see a white piece of nylon with two 10mm bolts. Those are what hold the ECU in the bracket. Remove bolts, pull down. ECU is now out. Technically, you can't see the ECU until you remove it. There is a black plastic cover that shields it from view.
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Race Director
Joined: Jun 2004
Posts: 13,957
Likes: 706
From: WI
Just a quick tip, the first time I removed the ecm on mine I used a mirror to look up at the bolts. All I did was sit along side the car and reach up with a 3" extension and it was out. I leave the drivers side bolt out now and just use the passenger side bolt as it is easier to see. I can drop the ecm now in just a few seconds without using the mirror.