250(2) Trouble indication
1In case of a trouble, the warning light will indicate. If the external trouble is a history trouble, the indication
will be cancelled. When the history trouble happens for no less than 5 times, the indicator light will remain
on even if there is no more trouble. "Low battery voltage" shall not be counted in the total number of
troubles.
2Only a service worker can reset a displayed or history trouble. The internal troubles of a SRS ECU
(HAE2.5) or the "crash record" of a trouble cannot be reset, in which case the SRS ECU (HAE2.5) shall
be replaced.
(3) Microcontroller-independent warning light on
Microcontroller with definitive troubles cannot fulfill its functions, thus cannot control the warning light. In
this case, the warning light will light up through proper circuit regardless of the microcontroller as stated
below:
yMalfunction of the battery supplying power to SRS ECU (HAE2.5): the warning lights are turned
on continuously by means of the drive function of the selfcheck light.
yLoss of internal working voltage: the warning light remains on.
yReset due to trigger failure of the watchdog: the warning light blinks.
yMicrocontroller out of work: the warning light always lights up.
yIncomplete insertion of SRS ECU (HAE2.5) connector: the warning light remains on by means of
a shorting bar.
The diagnostic procedures can well be illustrated as follows:
If it is found that the SRS warning light remains on, follow the undermentioned procedures to check even if
the light goes out eventually. First, a scan meter is used to check the location of the trouble.
Then£¬go on with the checking in accordance with specific methods and procedures for the correspondent
location.
a. If the result indicates that it is an internal trouble or that the SRS is already detonated, replace the
ECU directly.
b. Troubleshooting.
251Section 2 TroubleshootingI. LIST OF TROUBLES1. SRS warning light OFFDIAGNOSTIC PROCEDURESWhen performing the first diagnostic check, it is advised to shake slightly the harness and connector to see if
there is any discontinuous poor contact in circuit. If there is such a problem, make sure that the connections
of the connector, terminals and wire harness are correct and undamaged. Otherwise, follow these procedures:
(1) Check other wire harnesses and instrument cluster indicator lights
1Turn the ignition switch ON.
2Any other light on?
Yes: turn the ignition switch to LOCK, and continue with the next step.
No: check the power supply and ground system (fuse) of the instrument cluster, and continue with step 5.
(2) Check light bulb
CAUTION:
Mishandling of SRS components may release unexpectedly airbag and seat belt pretensioner, probably lead-
ing to a serious accident. Read the service cautions before handling a SRS component.
1Turn the ignition switch to LOCK.
2Disconnect the negative (-) terminal cable from the battery and wait for at least 60s.
3Remove the instrument cluster.
4Measure and see if the two pins of the SRS warning light is triggered.
Yes: continue with next step.
No: replace the bulb of the warning light.
Trouble Che c king Status P ossible Ca use
·Loss of voltage (fuse c irc uit bre a k)
·Instrument cluster trouble
·Trouble of wire harness between instrument
cluster and ECU SRS warning light OFF SRS wa rning c ircuit trouble1 SRS warning light is OFF SRS wa rning c irc uit trouble. No. Trouble shooting Ite ms De sc ription
2 SRS warning light re mains on SRS wa rning circ uit trouble or exte rna l trouble.
