AEM 30-6821 Series 2 Plug & Play EMS User Manual
Page 12
Page 12 of 21
Wiring accessories to the EMS
Please follow this suggested wiring diagram when adding new accessories and retaining
original accessories such as the multiplex coolant temperature gauge, air conditioning
switch, reverse lockout, UEGO gauges, MAP sensors, IAT sensors, or switches for use with
the EMS. Note that wire polarity is not important for the Air Temperature sensor.
+5V Sensor Power (tapped)
Sensor Ground (tapped)
MAP Signal
Sensor Ground (tapped)
O2 Sensor 1
Black (Sensor Ground)
Green (MAP Signal)
Red (+5V Sensor Power)
Black (Battery or chassis ground)
Red (+12V power, 5A fuse)
AEM UEGO
P/N: 30-5130
Brown (Analog - signal)
White (0-5V Analog + signal)
Pink (Switched +12V Power)
MAP Sensor
P/N: 30-2130-50
A5
A4, C31, or C35
A4, C31, or C35
C16
C22
IAT Sensor
Sensor Ground (tapped)
Air Temperature Sensor
P/N: 30-2010
A4, C31, C35
C13
Switch connects to GND
Ground
Switch 2 Input
C9
AEM EMS P/N:
30-6820 or 30-6821
30-1820 (Series 1) vs 30-6820 (Series 2) EMS differences:
The EMS functions assigned to certain pins have been changed and no longer match the 30-
1820 EMS. Unless otherwise noted, the following pins and functions will need to be manually
reconfigured after using AEMTuner to convert a 30-1820 Series1 EMS calibration for use
with the 30-6820 Series 2 hardware.
Pin Vehicle harness destination
30-1820 function
30-6820 function
Notes
A2
Front O2 sensor heater
Injector #5
---
Injector 5 moved to pin C2
A3
Front O2 sensor heater
Injector #6
---
Injector 6 moved to pin C1
A4
---
---
Sensor Ground
Additional spare output
A5
---
---
O2 #1
Additional spare output
B13
---
---
Coil 6
Additional spare output
B14
---
---
Coil 5
Additional spare output
B15
Ignition Control #4
Coil #5
Coil 4
Calibration must be updated
B26
Fuel Pump Control
Idle #1/2
Coil 8, LS 12
See ‘Fuel Pump Control’ on page 3
B28
---
---
CANH
B29
---
---
CANL
B34
---
---
HS1
C1
---
---
Injector 6
C2
---
---
Injector 5
C24
---
---
Knock 2
Additional spare input
D17
Main Relay control
FM
Coil 7
Use Coil7 settings in AEM startup cal