Two generations, one signal
Early 4G63 engines take their crank and cam signals from a single cam angle sensor (CAS) at the back of the cylinder head, above the flywheel. From the EVO 4 on, Mitsubishi moved the four-pulse crank signal onto the crankshaft itself, driven by a two-tooth wheel, and gave the cam its own sensor. The pattern the ECU sees is the same either way. The crank-mounted version just has better timing accuracy, because it avoids the slop in the timing belt.
| CAS engines (up to EVO 3) | EVO 4 onward | |
|---|---|---|
| Crank signal | Inside the CAS | Hall effect sensor at the crank |
| Cam signal | Inside the CAS | Hall effect sensor on the exhaust cam |
| Signal pattern | Four crank pulses, two cam pulses | Same pattern, so the same settings work |
| Notes | EVOs use an optical disc, other 4G engines a chopper wheel; the output is the same | The EVO 9 cam pattern is inverted, so it needs a different trigger pattern selected |
Wiring the CAS
| CAS pin | Carries | Haltech wire |
|---|---|---|
| 1 | The two-pulse cam signal | Home+ (yellow in the Home 4-core) |
| 2 | The four-pulse crank signal | Trigger+ (yellow in the Trigger 4-core) |
| 3 | 12V supply | Red in the Trigger 4-core |
| 4 | Ground | Signal ground (blue in the Trigger 4-core) |
The one-cable trick
The CAS doesn't use the Trigger- conductor at all. That green wire is sitting in the grey Trigger 4-core doing nothing, while the only thing you'd need from the grey/black Home 4-core is its Home+ wire. Move the green wire at the ECU end onto the Home+ pin, and the grey cable now carries power, ground, Trigger+ and Home+. One cable to the CAS instead of two.
| ECU | Remove and insulate | Move |
|---|---|---|
| Elite 550 / 750 / 950 | Yellow wire from pin A32 | Green wire from A33 to A32 |
| Elite 1000 / 1500 / 2000 / 2500 | Yellow wire from pin B2 | Green wire from B5 to B2 |
Label the green wire at both ends once you've done this, so the next person working on the car knows it's now carrying the cam signal.
Wiring the EVO 4-on crank and cam sensors
Both sensors are three-wire Hall effect parts with the same pin layout, so the only difference is which shielded cable they use:
| Sensor pin | Carries | Crank sensor to | Cam sensor to |
|---|---|---|---|
| 1 | Ground | Blue, Trigger 4-core | Blue, Home 4-core |
| 2 | Output signal | Yellow (Trigger+), Trigger 4-core | Yellow (Home+), Home 4-core |
| 3 | 12V supply | Red, Trigger 4-core | Red, Home 4-core |
The cam sensor reads off the exhaust camshaft.
When aftermarket cams go in, the cam trigger can end up installed backwards. If that happens, the cam signal moves by 360 crank degrees, so your TDC offset will be a full cycle out. If a freshly built engine won't fire or the timing light doesn't agree, check this before touching anything else.
Trigger settings
Haltech published separate trigger configuration screenshots for EVO 1 to 7 and for EVO 8 MR to 9. We can send them over, but we'd always confirm the result with a timing light rather than trusting any screenshot. Plug-in customers, for example with the Elite 2500 EVO 9 / EVO 8 MR adaptor harness kit, get these settings in the base map. The ESP trigger setup article explains each field.
Need this diagram? Ask us and we'll send it over with advice for your build.
Troubleshooting
| Symptom | Usually |
|---|---|
| No RPM while cranking | No 12V at the sensor, ground missing, or crank signal on the wrong wire |
| RPM shown but no sync | Cam signal not reaching Home+, often after the one-cable trick if the pin didn't seat |
| EVO 9 won't sync using an earlier EVO's trigger pattern | The inverted EVO 9 cam pattern needs its own trigger pattern |
| Timing a full cycle out after new cams | Cam trigger installed backwards |
For everything else on this engine, see the 4G63 engine guide and what makes the 4G63 special.
