Multiplex Integrated Control System: Diagnosis Acura RDX I facelift

Troubleshooting CAN Circuit Related Problems

Note. Check the PCM for DTCs and troubleshoot PCM (see GENERAL TROUBLESHOOTING INFORMATION ) or F-CAN loss of communication errors first.

Using the B-CAN System Diagnosis Test Mode 1 (Use only if the HDS is unavailable)

1. Check for communication circuit problems using the B-CAN System Diagnostic Test Mode 1 (see «TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE 1 AND TEST MODE 2 (WITHOUT THE HDS)»(ref-513878-S10316809042012111600000) ).
2. Check for DTCs.
3. If multiple DTCs are stored, sort them, and then troubleshoot the DTCs in this order. Battery voltage DTCs Internal error DTCs Loss of communication DTCs NOTE: If DTC B1000 is stored, troubleshoot DTC B1000 (see «DTC B1000: COMMUNICATION CIRCUIT ERROR (BUS-OFF)»(ref-513878-S33467679332012111600000) ) first. Signal error DTCs
4. If no DTCs are retrieved, use the B-CAN System Diagnostic Test Mode 2 to check all inputs related to failure (see step 10 ).

How to Clear the DTC

1. Enter B-CAN System Diagnosis Test Mode 1 (see «TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE 1 AND TEST MODE 2 (WITHOUT THE HDS)»(ref-513878-S10316809042012111600000) ).
2. While in Test Mode 1, press and hold down the SEL/RESET button for at least 10 seconds to clear the DTCs.

Loss of Communication DTC Cross-Reference Chart

When an ECU on the CAN circuit is unable to communicate with the other ECUs on the CAN circuit, the other control units set loss of communication DTCs. Use this chart to find the control unit that is not communicating with the other control units on the CAN circuit.

1. Find the Transmitting Control Unit that is in the same row as all of the loss of communication DTCs retrieved.
2. Do the input tests for the Transmitting Control Unit.

BUS OFF AND INTERNAL ERROR CODES

LOSS OF COMMUNICATION

DTC Troubleshooting Index

Note. Check the PCM for DTCs and troubleshoot PCM (see GENERAL TROUBLESHOOTING INFORMATION ) or F-CAN loss of communication errors first, then record all DTCs and sort them by DTC type using the following DTC troubleshooting indexes, then troubleshoot the DTC (s) in this order.

1. Battery voltage DTCs
2. Internal error DTCs
3. Loss of communication DTCs (beginning with the lowest number first; for example, if B1008 and B1011 are retrieved, troubleshoot B1008 first).
4. Signal error DTCs

MICU

GAUGE CONTROL MODULE

AUTOMATIC LIGHTING CONTROL UNIT

CLIMATE CONTROL UNIT

HANDSFREELINK CONTROL UNIT

POWER SEAT CONTROL UNIT

IMMOBILIZER-KEYLESS CONTROL UNIT

ACURALINK® CONTROL UNIT (XM RECEIVER)

Sleep and Wake-Up Mode Test

1. Shift to the sleep mode: Close all doors. Turn the ignition switch to LOCK (0) and remove the key, then open and close the driver's door. If the MICU receives no signals from the inputs listed below, it will go into sleep mode in less than 50 seconds. IG1 power supply IG2 power supply B-CAN data Tailgate latch switch (Tailgate closed) (OFF) Hazard warning switch (OFF)
2. Confirm the sleep mode: NOTE: Check any official Honda service website for more service information about parasitic draw at the battery. Check the parasitic draw at the battery while shifting into the sleep mode; amperage should change from about 200 mA to less than 35 mA in less than 50 seconds.
3. Shift to the wake up mode: When the ignition switch is turned to ON (II), the MICU, the gauge control module, the immobilizer-keyless control unit, and the PCM wake up at the same time without "talking" to each other through the communication lines. When any switch in the multiplex integrated control system is turned on, it wakes up its related control unit which, in turn, wakes up the other units. After confirming the sleep mode, look in the following table for the switch most related to the problem. Operate that switch and see if its control unit wakes up. NOTE: If any control unit is faulty and does not wake up, several circuits in the system malfunction at the same time. Below is a list of the switches and input signals that can wake them up. IG1 power supply IG2 power supply B-CAN data Door switches (door open) Driver's door lock switch (LOCK or UNLOCK) Driver's door lock knob switch (LOCK or UNLOCK) Driver's door key cylinder switch (LOCK or UNLOCK) Front passenger's door lock switch (LOCK or UNLOCK) Front passenger's door lock knob switch (LOCK or UNLOCK) Left rear door lock knob switch Right rear door lock knob switch Tailgate latch switch (Tailgate open) Security hood switch (hood open) Hazard warning switch (ON) Combination light switch (Parking, Headlight, Dimmer, Passing ON) Ignition key switch (key inserted)

Scheme 3

Scheme 4

Scheme 5

Scheme 6

DTC-B1011: MICU Lost Communication With Gauge Control Module (VSP/NE message)

Note. If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

1. Clear the DTCs with the HDS.
2. Turn the ignition switch to LOCK (0) and then back to ON (II).
3. Wait for at least 6 seconds.
4. Check for DTCs with the HDS. Is DTC B1011 indicated? YES -Go to step 5. NO -Intermittent failure, the gauge control module is OK at this time. Check for loose or poor connections at the gauge control module 36P connector and at under-dash fuse/relay box connector Q (16P). If the connections are good, check the battery condition (see «BATTERY TEST»(ref-513852-S37711115492012111600000) ) and the charging system (see «SYMPTOM TROUBLESHOOTING INDEX»(ref-513847-S02731401002012111600000) ).
5. Check for DTCs with the HDS. Are DTCs B1008 and B1032 also indicated with DTC B1011? YES -Check for an open or high resistance in the communication circuit between the MICU and the gauge control module. If the circuit is faulty, repair the open or high resistance. If the circuit is OK, faulty MICU, replace the under-dash fuse/relay box (see «REMOVAL AND INSTALLATION»(ref-513873-S08992568522012111600000) ). NO -Go to the gauge control module input test (see «GAUGE CONTROL MODULE INPUT TEST»(ref-513857-S26173344952012111600000) ).

MICU Input Test

Note. Before testing, troubleshoot the multiplex integrated control unit (MICU) first, using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

Scheme 7

Scheme 8

1. Turn the ignition switch to LOCK (0).
2. Remove the driver's dashboard undercover (see «CENTER PANEL REMOVAL/INSTALLATION»(ref-513880-S11215136062012111600000) ).
3. Check the No. 10 (7.5 A) fuse in the under-dash fuse/relay box. If the fuse is blown, replace it and go to step 4.
4. Disconnect under-dash fuse/relay box connectors E, F, G, K, and T. NOTE: All connector views are shown from wire side of female terminals.
5. Inspect the connector and socket terminals to be sure they are all making good contact. If the terminals are bent, loose or corroded, repair them as necessary and recheck the system. If the terminals look OK, go to step 6.
6. With the connector still disconnected, do the following input tests. If any test indicates a problem, find and correct the cause, then recheck the system. If the input test proves OK, go to step 7. Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained K4 PNK Under all conditions (Interior light switch and ceiling light switch in DOOR position) Attach to ground: The ceiling light should come on. Blown No. 22 (7.5 A) fuse in the under-hood fuse/relay box Blown bulb(s) Faulty interior light switch Faulty ceiling light An open or high resistance in the wire
7. Reconnect the connectors to the under-dash fuse/relay box, and do the following input tests. If any test indicates a problem, find and correct the cause, then recheck the system. If all the input tests prove OK, the MICU must be faulty; replace the under-dash fuse/relay box (see «REMOVAL AND INSTALLATION»(ref-513873-S08992568522012111600000) ). Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained G2 GRN Under all conditions Measure the voltage to ground: There should be battery voltage. Blown No. 23 (10 A) fuse in the under-hood fuse/relay box An open or high resistance in the wire E6 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V. Poor ground (G601) An open or high resistance in the ground wire E33 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V. Poor ground(G601) An open or high resistance in the ground wire F20 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V. Poor ground(G451) An open or high resistance in the ground wire T34 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V. Poor ground(G501) An open or high resistance in the ground wire