The “stomp test” is a simple procedure performed to determine the cause of a Check Engine Light (CEL) on a number of vehicles that used the Motronic 1.3 and 1.7 ECUs (such as the 1988-1992 E30 325i) and Motronic 3.x (such as 1991-1995 E36 325i). Motronic 1.3/1.7 ECUs include 173, 175, 179, 282, 380, 381, 524, 525, and 526. 3.x include 402, 403, 404, 413, and 506,

The procedure for performing the stomp test on Motronic 1.3/1.7 is as follows:

  1. Get in your vehicle and shut all doors/trunk.
  2. Turn key to “ON” position, but do not start the vehicle.
  3. Fully depress the accelerator pedal, then completely release for between 0.5 and 1.0 seconds. Repeat this a total of 5 times within 10 seconds.
  4. The CEL will flash once, then it will flash a Fehler Lampen Ort, or Fault Light Code (FLC).
  5. The code will flash as a succession of blinks, with a short pause between each number.
    1. eg. “blink-blink-pause, blink-pause, blink-blink-blink-pause, blink-pause” would be code “2-1-3-1”
    2. If there are no faults, it will flash the code “1444” (for 4, 6, and 8 cylinder engines) or “2444” (for 12 cylinder engines).

The procedure for performing the stomp test on Motronic 3.x is very similar, but differs in the following ways:

  1. The time between key and pedal action must be shorter.
  2. The pedal must be depressed, released, and repeated in quicker succession.
  3. It is a bit trickier and may take a few attempts.

The error codes are as follows:

Malfunctioning System. Fault Code Comments.

ECU

1211

ECU component failure or bad chip.

Air Mass/Volume Sensor

1215

Throttle Potentiometer

1216

Output Stage, Group 1

1218

Output Stage, Group 2

1219

EGO(O2) Sensor 1

1221

EGO(O2) Sensor 2

1212

Lambda Control 1

1222

Lambda Control 2

1213

Coolant Temp. Sensor

1223

Intake Air Temp. Sensor

1224

Knock Sensor 1

1225

Knock Sensor 2

1226

Knock Sensor 3

1227

Knock Sensor 4

1228

Battery Voltage/DME Main Relay

1231

Throttle Idle Switch

1232

Throttle WOT Switch

1233

Speedometer A Signal

1234

A/C Compressor cut off

1237

A/C Compressor

1242

Crankshaft Pulse Sensor

1243

Camshaft Sensor

1244

Intervention AEGS

1245

Ignition Secondary Monitor

1247

Fuel Injector 1 (or group 1)

1251

Fuel Injector 2 (or group 2)

1252

Fuel Injector 3

1253

Fuel Injector 4

1254

Fuel Injector 5

1255

Fuel Injector 6

1256

Fuel Injector 7

1257

Fuel Injector 8

1258

Fuel Pump Relay Control

1261

Idle Speed Actuator

1262

Purge Valve

1263

EGO Heater

1264

Fault Lamp (check engine)

1265

VANOS

1266

Air Pump Relay Control

1267

Ignition Coil 1

1271

Ignition Coil 2

1272

Ignition Coil 3

1273

Ignition Coil 4

1274

Ignition Coil 5

1275

Ignition Coil 6

1276

Ignition Coil 7

1277

Ignition Coil 8

1278

Control Unit Memory Supply

1281

Fault Code Memory

1282

Fuel Injector Output Stage

1283

Knock Control test Pulse

1286

No Failures

1444