2004 Impala : my notes and wiring

2004 Chevrolet Impala

Just did this car. Though this might help some of you.

Car is pretty straight forward however there are several relays and diodes required, and a 555L
Unlike previous Impalas where access to ignition wires is obstructed by the upper dash these are easy to get to.
Factory alarm must be dealt with – disarm wire.
The domelight superv also MUST be connected – two wires diode isolated (to allow unlock after module goes to sleep – set unlock to double pulse)
.
Relays are as follows.:

Door lock
GROUND and 470ohm resistor to #87    
12 VOLTS to #85
BRAIN output lock #86
BCM lock/unlock wire #30


Door Unlock
GROUND to #87    
12 VOLTS to #85
BRAIN output unlock to #86
BCM lock/unock wire to #30


3rd Ignition
12 VOLTS to #87
12 VOLTS to #85
BRAIN output ign 3 to #86
IGN 3 (brown on this car)

Domelight
GROUND to #87
12 VOLTS to #85
BRAIN output dome to #86
BCM dome –two wires diode isolated to #30

555L
GROUND
12 VOLTS
BRAIN output(ign 3)
IGN (pink)
IGN ( cut 18ga yellow - key side)
IGN ( cut 18ga yellow – car side)

Wires that do NOT go to BCM are

Park lights -     Light Blue at SWITCH      left side of dash
Trunk -      Black at SWITCH          left side of dash
Brake -      White at SWITCH          above brake pedal
Horn -           Black at Strng Clmn          above brake pedal

Wires that DO go to BCM are:
These wires can be found in the taped up harness running to the left of the steering column.

Lock/Unlock      - Orange Black
Domelights      - Blue and Blue white diode isolated
Disarm          - Light Green

Wires to Ignition are:
12 VOLTS -Red
IGNITION 1 -Pink
IGNITION 2 - Green
ACCESSORY – Orange
Ignition 3 from relay – Brown
555L cut wire – Yellow 18ga


Wires through firewall are:
TACH – to white wire at 8 pin connector under engine cover (comes off easy). This is the white wire next to a pink at the bottom of the connector.
HOODPIN – use an L Bracket on driver’s side next to air filter (plenty of room)

Also don't forget to add a diode for the emergency brake. I had my wife's car done and if you set the emergency brake the alarm goes off after ten minutes. Not sure what was meant, but the shop called DEI and he said he had to add a diode. I am going to take the car  by the shop next week and get it fixed also I will let them know about the double pulsing the unlock, because her car goes to sleep and we have to use the key to get in.

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bassop